tag:blogger.com,1999:blog-14075316016428150942024-03-19T04:47:33.856-04:00Animal Endocrine ClinicThe only veterinary hospital in the world devoted exclusively to the diagnosis and treatment of dogs and cats with endocrine (hormonal) problems.Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.comBlogger191125tag:blogger.com,1999:blog-1407531601642815094.post-18695642546349967142015-06-11T10:00:00.002-04:002015-06-11T10:00:55.488-04:00Diagnosing Hypothyroidism in Dogs<div class="separator" style="clear: both; text-align: center;">
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I have a 7-year old spayed Golden Retriever who weighs about 110 lbs. No signs of hypothyroidism except for being overweight with a borderline high serum cholesterol concentrations (256 mg/dl).
The serum T4 value was slightly low at 0.9 µg/dl (reference interval, 1.0-4.0 µg/dl).<br />
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Is this slightly low serum T4 concentration diagnostic for hypothyroidism? Would you start her on levothyroxine (L-T4) and retest T4 levels in a month?<br />
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I'd appreciate your thoughts and recommendations.<br />
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<b>My Response: </b><br />
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I would never base the diagnosis on only a resting serum T4 value alone. We commonly find low values that fluctuate in and out of the reference range in dogs that are clinically normal and never develop hypothyroidism. In addition, most non-thyroidal illness will lower the total T4 values in dogs, and these dogs would not benefit from thyroid hormone supplementation (1). It certainly doesn't sound like your dog is sick or acting ill in any way, so this latter explanation probably doesn't apply here.<br />
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For your dog, I'd recommend that your veterinarian collect more sera to do a complete thyroid panel, which should include the following tests (2-4):<br />
<ul>
<li>Serum T4 concentration</li>
<li>Serum T3 concentration</li>
<li>Serum free T4 by dialysis</li>
<li>Serum TSH concentration</li>
<li>Serum levels of thyroglobulin autoantibodies</li>
</ul>
If you have it available in your area, thyroid scintigraphy (nuclear medicine scan) is actually the best and most accurate way to diagnose hypothyroidism in dogs (4.5).<br />
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<b> References: </b><br />
<ol>
<li>Kantrowitz LB, Peterson ME, Melian C, et al. <a href="http://www.ncbi.nlm.nih.gov/pubmed/11561650" target="_blank">Serum total thyroxine, total triiodothyronine, free thyroxine, and thyrotropin concentrations in dogs with nonthyroidal disease</a>. J Am Vet Med Assoc 2001;219:765-769. </li>
<li>Peterson ME, Melian C, Nichols R. <a href="http://www.ncbi.nlm.nih.gov/pubmed/9394888" target="_blank">Measurement of serum total thyroxine, triiodothyronine, free thyroxine, and thyrotropin concentrations for diagnosis of hypothyroidism in dogs</a>. J Am Vet Med Assoc 1997;211:1396-1402. </li>
<li>Nachreiner RF, Refsal KR, Graham PA, et al. <a href="http://www.ncbi.nlm.nih.gov/pubmed/11860240" target="_blank">Prevalence of serum thyroid hormone autoantibodies in dogs with clinical signs of hypothyroidism</a>. <i>J Am Vet Med Assoc</i> 2002;220:466-471. </li>
<li>Diaz Espineira MM, Mol JA, Peeters ME, et al. <a href="http://www.ncbi.nlm.nih.gov/pubmed/17338146" target="_blank">Assessment of thyroid function in dogs with low plasma thyroxine concentration</a>. J Vet Intern Med 2007;21:25-32. </li>
<li>Shiel RE, Pinilla M, McAllister H, et al. <a href="http://www.ncbi.nlm.nih.gov/pubmed/22533320" target="_blank">Assessment of the value of quantitative thyroid scintigraphy for determination of thyroid function in dogs</a>. J Small Anim Pract 2012;53:278-285. </li>
</ol>
Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com5tag:blogger.com,1999:blog-1407531601642815094.post-4989375377352114892014-11-14T10:05:00.000-05:002014-11-14T10:05:54.408-05:00World Diabetes Day: November 14 2014<div style="text-align: center;">
<b><span style="color: red;">Today, November 14th, is World Diabetes Day</span></b></div>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjuEkYLrpzJ_6ruXMD5cEUEcL7_ddSzD_ScFThksdhvdTzowmHbrMgF38SGS1NMuV8KJueXlAauM-Z1-2lOPJiyp0mdv8g1q0VyV4eFBbhFYII3oSSiYy5KYTVQJ4jKxkL5M8TKd0pNj3M/s1600/WDD+agina.jpg" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjuEkYLrpzJ_6ruXMD5cEUEcL7_ddSzD_ScFThksdhvdTzowmHbrMgF38SGS1NMuV8KJueXlAauM-Z1-2lOPJiyp0mdv8g1q0VyV4eFBbhFYII3oSSiYy5KYTVQJ4jKxkL5M8TKd0pNj3M/s1600/WDD+agina.jpg" height="141" width="200" /></a>World Diabetes Day is the primary global awareness campaign of the diabetes mellitus world and is held on November 14 of each year (1). It was introduced in 1991 by the International Diabetes Federation and the World Health Organization in response to the alarming rise of human diabetes around the world.<br />
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World Diabetes Day is a campaign that features a new theme chosen by the International Diabetes Federation each year to address issues facing the global diabetes community. This year's campaign theme is "<span style="background-color: white; color: #333333; font-family: inherit; line-height: 19.5px;">Healthy Living and Diabetes"(1)</span><span style="background-color: white; color: #333333; font-family: inherit; line-height: 19.5px;">.</span><br />
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While the campaigns last the whole year, the day itself marks the birthday of <a href="http://en.wikipedia.org/wiki/Frederick_Banting" target="_blank">Frederick Banting</a> who, along with Charles Best, first conceived the idea which led to the discovery of insulin in 1922 (2). You can also find out more about Frederick Banting in Wouter de Herder's review Heroes in Endocrinology: Nobel Prizes (3).<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjfowgI3xiTObhfFvrPT2ZQ5S6L__L9TDznP3FH-tbF-8dGIkPlLC4Zlc1MGlwbW6IaisexxiMe2oM1A8aF7oCgvkUzkSHAedovI6Gzm7dUAXajRtlELBwmx9pD8_lqB-mGhh-bHsGAFl8/s1600/banting_best_photo.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjfowgI3xiTObhfFvrPT2ZQ5S6L__L9TDznP3FH-tbF-8dGIkPlLC4Zlc1MGlwbW6IaisexxiMe2oM1A8aF7oCgvkUzkSHAedovI6Gzm7dUAXajRtlELBwmx9pD8_lqB-mGhh-bHsGAFl8/s1600/banting_best_photo.jpg" height="400" width="296" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><b style="background-color: white; color: #171616; font-family: Verdana, Geneva, sans-serif; font-size: 11px; line-height: 18px;">Charles H. Best and Frederick G. Banting (on right) with one of the diabetic dogs used in their studies of insulin</b></td></tr>
</tbody></table>
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In the past few years, diabetes rates among our pets in the U.S. have increased roughly 33% among dogs and 16% among the nation's cat population, per a national analysis of pet health (4). This emphasizes the importance of this disorder in our cats and dogs as well as human patients with diabetes.
To successfully manage diabetes in animals, one must understand the disease and monitor and provide daily treatments to the cat or dog with diabetes. Treatment involves a combination of weight loss (if obese), diet, and insulin injections generally twice daily.<br />
<br />
<b>References </b><br />
<ol>
<li>World Diabetes Day – <a href="http://www.idf.org/wdd-index" target="_blank">Official website</a>.</li>
<li>Frederick Grant Banting (1891-1941), codiscoverer of insulin. Journal of the American Medical Association 1966;198:660-661. </li>
<li>de Herder WW. <a href="http://www.endocrineconnections.com/content/3/3/R94.full" target="_blank">Heroes in endocrinology: Nobel Prizes</a>. Endocr Connect. 2014;3:R94-R104. doi: 10.1530/EC-14-0070. </li>
<li>Washburn L. Human health risks on the rise in animals. The Record. April 20, 2011. </li>
</ol>
Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com0tag:blogger.com,1999:blog-1407531601642815094.post-80547098987109221462014-10-28T11:45:00.000-04:002014-10-28T12:11:17.598-04:00Dr. Peterson Presented with Outstanding Speaker of the Year Award<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
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<span style="background-color: white; color: #0d0c0c; font-family: Verdana; font-size: 12px; letter-spacing: 0.280000001192093px; line-height: 18px;">Dr. Peterson was awarded the Outstanding Speaker of the Year Award on Saturday, October 11 at the New York State Veterinary Conference Celebration Dinner. </span><br />
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<span style="background-color: white; color: #0d0c0c; font-family: Verdana; font-size: 12px; letter-spacing: 0.280000001192093px; line-height: 18px;">The award was presented to him by the New York State Veterinary Medical Society and Cornell University College of Veterinary Medicine.</span><br />
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<tr><td class="tr-caption" style="text-align: center;">Dr. Peterson celebrates by dancing with Jennifer Mauer of the NY State VMS. </td></tr>
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Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com0tag:blogger.com,1999:blog-1407531601642815094.post-46320924077269369392014-10-07T12:45:00.000-04:002014-10-07T12:45:46.229-04:00National Pet Obesity Awareness Day<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiJDQtZZPtZtiXSYosKmXljmPaU2TO9KUrku1kyNhhyphenhyphen_ZSKUGlH8aLYabcfV8BE1jUn0gGACKWlngpH35ucsEQSSmG9VBpul3tgBUiw8OCVHpUAj0I9G7Ofq0ONfNWBO4CSUUpuKwvcWTA/s1600/fatcat1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiJDQtZZPtZtiXSYosKmXljmPaU2TO9KUrku1kyNhhyphenhyphen_ZSKUGlH8aLYabcfV8BE1jUn0gGACKWlngpH35ucsEQSSmG9VBpul3tgBUiw8OCVHpUAj0I9G7Ofq0ONfNWBO4CSUUpuKwvcWTA/s1600/fatcat1.jpg" height="283" width="320" /></a></div>
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On Wednesday, October 8, 2014, the Association for Pet Obesity Prevention (APOP) will conduct its Eighth Annual Pet Obesity Awareness Day survey in an effort to more accurately determine the exact number of pets in the United States that are overweight or obese. Pet owners and veterinarians are encouraged to participate in the study.<br />
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Please visit the <a href="http://www.petobesityprevention.org/2014-national-pet-obesity-awareness-day/" target="_blank">APOP website</a> to learn more, as well as to participate in this important study.<br />
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<b>Links: </b><br />
Association for Pet Obesity Prevention website. <a href="http://www.petobesityprevention.org/">www.petobesityprevention.org</a>Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com0tag:blogger.com,1999:blog-1407531601642815094.post-78371099975452570222014-09-18T08:13:00.003-04:002014-09-18T08:13:45.521-04:00Your Thyroid: What You Need to Know<span style="background-color: white; color: #171616; font-family: Verdana, Geneva, sans-serif; font-size: 13px; line-height: 18.4799995422363px;">I came across this information sheet about "Your Thyroid," which came from the Hormone Health Network. Although very simplistic, this still makes it clear that the thyroid gland and it's thyroid hormone secretion is very important for overall body function. It also helps clarify the regulatory feedback system between the pituitary gland (secreting TSH) and the thyroid gland (secreting T4 and T3). </span><br />
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For more information and fact sheets about specific thyroid diseases, <a href="http://www.hormone.org/diseases-and-conditions/thyroid" target="_blank">click here</a>. To learn more about other endocrine glands and their diseases, visit the Hormone Health Network website at <a href="http://www.hormone.org/">http://www.hormone.org</a>.<br />
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhZzj_dbWKpt0U2V-Imdt2BskNog2RGn5xP-R4yBow6Y-OEIHqD6GHKMl58bZBDmJpXYYk5dFyGJBEcEWOvwLKxqKsn2gcoL6PYuu8dpUn-c21iLW-lAZ0f8PMtjdFRn2K24Dk14KQ4Ktc/s1600/Your+Thyroid+copy.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhZzj_dbWKpt0U2V-Imdt2BskNog2RGn5xP-R4yBow6Y-OEIHqD6GHKMl58bZBDmJpXYYk5dFyGJBEcEWOvwLKxqKsn2gcoL6PYuu8dpUn-c21iLW-lAZ0f8PMtjdFRn2K24Dk14KQ4Ktc/s1600/Your+Thyroid+copy.jpg" height="640" width="468" /></a></div>
<br />Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com0tag:blogger.com,1999:blog-1407531601642815094.post-2432496052658200782014-09-09T10:09:00.002-04:002014-09-09T10:09:36.369-04:00Dr. Peterson Interviewed in the Journal of Feline Medicine and Surgery<div class="separator" style="clear: both; text-align: center;">
<a href="http://www.animalendocrine.com/wp-content/uploads/2014/09/My-interview.pdf" style="clear: left; float: left; margin-bottom: 1em; margin-right: 1em;" target="_blank"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiHMz9Uhih5GVflt5abCwfhBHm4f_RIkSFYqiqwkzQSDvoCOqSWRUgW9wj5e2tEJPMrANTCHXLDe13v6MRy0TxKyylj416ygKzkaexqAx5SKkVrM7T0zUegcxNpEfB-6RCXimeAXs12j8Y/s1600/Screen+Shot+2014-09-09+at+10.02.36+AM.png" height="320" width="239" /></a></div>
Dr. Peterson was interviewed for the September issue of the Journal of Feline Medicine and Surgery.<br />
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The interview provides some interesting insights into Dr. Peterson's career, his own cats, and his aspirations and goals as he continues his research.<br />
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<a href="http://www.animalendocrine.com/wp-content/uploads/2014/09/My-interview.pdf" target="_blank">Click here to download and read the full interview.</a>Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com0tag:blogger.com,1999:blog-1407531601642815094.post-88872038348161714792014-07-22T10:26:00.000-04:002014-07-22T10:26:01.373-04:00Dr. Peterson Interviewed for Dog Fancy Article About Insulin Pen for Dogs<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhy3QOuCYT2A6nMaDwTo0qgPqbvPOqqstDJVnSAdiw8uQwVXe8MbMfO2ms3FhRHbeqeMN5XvULqOpb9oKuWSZvRbTck85NXiTQlYUmhfQT5ubo0n__uXmD8otHf8HVAOLfYUCyAGwvHGNA/s1600/dogfancy_FDA_insulin_article.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhy3QOuCYT2A6nMaDwTo0qgPqbvPOqqstDJVnSAdiw8uQwVXe8MbMfO2ms3FhRHbeqeMN5XvULqOpb9oKuWSZvRbTck85NXiTQlYUmhfQT5ubo0n__uXmD8otHf8HVAOLfYUCyAGwvHGNA/s1600/dogfancy_FDA_insulin_article.jpg" height="355" width="400" /></a></div>
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Dr. Peterson was interviewed for the September 2014 issue of <a href="http://www.dogchannel.com/dog-magazines/dogfancy/default.aspx" target="_blank">Dog Fancy</a> (pictured above). Merck Animal Health has just received approval from the FDA to sell their <a href="http://www.vetsulin.com/" target="_blank">VetPen product</a>, the first insulin injection pen available for diabetic dogs and cats, and Dr. Peterson weighed in on the benefits of such an easy-to-use device.Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com0tag:blogger.com,1999:blog-1407531601642815094.post-62703349459044056382014-05-26T14:07:00.000-04:002014-05-26T14:07:42.877-04:00Celebrate the Seventh Annual World Thyroid Day<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi1taO7BDSICi_Wx9gdVJd7LfH9WHHJStejPr5yR1TtlbjhEhCL4UL4bzKcGZ4pFtVA14BP1NR_lJy7rwy6kNOG5WJmO9BEohqqLQmaRVzVFc-qHAW8AVYQ46V417u9Bfoi-IJ02MWyPas/s1600/World+THyroid+Day.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi1taO7BDSICi_Wx9gdVJd7LfH9WHHJStejPr5yR1TtlbjhEhCL4UL4bzKcGZ4pFtVA14BP1NR_lJy7rwy6kNOG5WJmO9BEohqqLQmaRVzVFc-qHAW8AVYQ46V417u9Bfoi-IJ02MWyPas/s1600/World+THyroid+Day.jpg" height="200" width="175" /></a></div>
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<span style="text-align: left;">It's not just cats and dogs that develop thyroid disease. Approximately 750 million people worldwide are affected by thyroid disorders, and the Seventh Annual World Thyroid Day, being held this weekend, has 5 major goals, say the organizations who support it. These include the American Thyroid Association (ATA), the European Thyroid Association, the Asia Oceania Thyroid Association, and the Latin American Thyroid Society.</span></div>
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The thyroid gland produces hormones that regulate the body's metabolism and influence every cell, tissue, and organ in the body, they point out. Hypothyroidism is characterized by symptoms of fatigue, depression, and forgetfulness, while hyperthyroidism is associated with irritability, nervousness, and muscle weakness. <br />
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The aims of World Thyroid Day are the following:<br />
<ul>
<li>Increase awareness of thyroid health. </li>
<li>Promote understanding of advances made in treating thyroid diseases. </li>
<li>Emphasize the prevalence of thyroid diseases. </li>
<li>Focus on the urgent need for education and prevention programs.</li>
<li>Expand awareness of new treatment modalities.</li>
</ul>
The thyroid gland, butterfly-shaped and located in the middle of the lower neck, produces hormones that influence every cell, tissue and organ in the body. The thyroid hormones regulate the body's metabolism—the rate at which the body produces energy from nutrients and oxygen—and affects critical body functions, such as energy level and heart rate.<br />
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The thyroid also plays a critical role during pregnancy, the thyroid societies explain. Consequently, the ATA recommends that pregnant women at high risk for thyroid disease should have their thyroid function tested early in their pregnancy. Another important issue is thyroid cancer, which is rapidly increasing, according to the ATA, which says there were 44,670 new cases of thyroid cancer recorded in 2010 in the United States. <br />
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But when thyroid cancer is identified and treated early, "the majority of patients can be completely cured," the American Thyroid Association stresses. The organization also notes that it is important to distinguish thyroid cancer from benign thyroid nodules, which are common in the population. <br />
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Patient education on human thyroid conditions can be found on the ATA website at <a href="http://www.thyroid.org/patient-thyroid-information/">http://www.thyroid.org/patient-thyroid-information/</a>.Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com0tag:blogger.com,1999:blog-1407531601642815094.post-8503073968642976722014-05-22T14:52:00.000-04:002014-05-22T14:52:08.878-04:00Insect Repellent, Antiviral Drug Detected in Jerky Pet Treats for Dogs<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj7XNtATfU1n5OQP2u2YI7CkQm8r7j7LnKifcb2ET-FYITyP1at25BDl5PeFe1x-fLZXwk1THYSEfTva_WJ-4UcGzcBWA8ZfZ-AoBKhhHuTi_wIXbTvZfnvmpJA16PNp-f_KNMVJ25TAO0/s1600/dog+treats.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj7XNtATfU1n5OQP2u2YI7CkQm8r7j7LnKifcb2ET-FYITyP1at25BDl5PeFe1x-fLZXwk1THYSEfTva_WJ-4UcGzcBWA8ZfZ-AoBKhhHuTi_wIXbTvZfnvmpJA16PNp-f_KNMVJ25TAO0/s1600/dog+treats.jpg" height="256" width="320" /></a></div>
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Chicken jerky treats consumed by dogs that became sick over the past few month have now been found to be tainted by the insect repellent N,N-diethyl-meta-toluamide, better known as <a href="http://www.epa.gov/pesticides/factsheets/chemicals/deet.htm" target="_blank">DEET</a>, as well as the antiviral drug <a href="http://en.wikipedia.org/wiki/Amantadine" target="_blank">amantadine</a>. <br />
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This is according to a veterinary pathologist leading an independent probe of the ongoing pet treat mystery. For more information, click this <a href="http://news.vin.com/VINNews.aspx?articleId=32153" target="_blank">link</a> to read the article by the Veterinary Information Network News Service. Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com1tag:blogger.com,1999:blog-1407531601642815094.post-26936075059327185002014-04-04T13:48:00.000-04:002014-04-04T14:51:56.943-04:00Insulin Injection Pen (VetPen): More Questions (and Answers) about this New Diabetic Product<br />
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiF_5C70PTOZGrqrL9SvUcUS8pm5VQYcCSDm7aCPjc31ZsCRVTMwe6pOqkHhE3vkuIIcxBGpX5fFDWFCFLiMagnzYzmPy43RFrIjSYqw_mSlVUMwjRZJ5o_mTQEHbk-x_7ezbzsij-6WDA/s1600/Vet+Pen.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiF_5C70PTOZGrqrL9SvUcUS8pm5VQYcCSDm7aCPjc31ZsCRVTMwe6pOqkHhE3vkuIIcxBGpX5fFDWFCFLiMagnzYzmPy43RFrIjSYqw_mSlVUMwjRZJ5o_mTQEHbk-x_7ezbzsij-6WDA/s1600/Vet+Pen.png" height="282" width="400" /></a></div>
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Since the FDA approved the use of a new insulin injection pen (VetPen) made by Merck Animal Health last week (1,2), I've received a number of questions from both veterinarians and owners of diabetic pets. Listed below are some of the most common questions with my responses.<br />
<br />
<b>Do we buy a single VetPen and use it forever? Or does the VetPen have to be replaced after a month or two?</b><br />
<br />
The VetPen has been tested for at least 3,000 actuations (i.e., how many times the insulin release button is pressed and released). Therefore, a single VetPen is likely to last a lifetime for the majority of dogs and cats treated with diabetes.<br />
<br />
<b>How are the pens and cartridges sold? </b><br />
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjlWpOgykKgQK6GvCA5Fd5FuUYuDfLsjyaMy8LcuHD2deaf3wfltSAXceqcGtTPgOZe8QkJkFOzl9xb-bAPIMU36UmXM6mqJtZAx8QLUli7HqrtOEQvIP0lk90lVkrmDefbFd_rqq5ssh0/s1600/VetPen+-+2+sizes.png" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjlWpOgykKgQK6GvCA5Fd5FuUYuDfLsjyaMy8LcuHD2deaf3wfltSAXceqcGtTPgOZe8QkJkFOzl9xb-bAPIMU36UmXM6mqJtZAx8QLUli7HqrtOEQvIP0lk90lVkrmDefbFd_rqq5ssh0/s1600/VetPen+-+2+sizes.png" height="320" width="152" /></a>The reusable VetPen is supplied in a Starter Kit which contains everything you need to get started (see below). This included everything except the Vetsulin cartridges, which are supplied separately in cartons of ten, 2.7-mL cartridges.<br />
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The VetPen itself is available in 2 sizes. For greater accuracy at low doses, the first option (blue cap) has a maximum total dose of 8 units, allowing for dosing increments of 0.5 unit per injection. If higher insulin doses are being administered, the second VetPen option (tan cap) has a maximum total dose of 16 IU per injection, with dosing increments of 1 unit.<br />
<br />
<b>What is in each VetPen Starter Kit?</b><br />
Each Starter Kit contains either an 8-unit or 16-unit VetPen with an instruction leaflet.<br />
<br />
The kit also contains a box of 28-g, ultra-thin needles that feature a silicone coating to help minimize injection discomfort, as well as a needle remover that helps to remove used needles, while minimizing the risk of accidental needle stick injury. There is also a travel pouch to hold all of the components.<br />
<br />
The kit also contains two adaptors to assist those with dexterity issues. The dose selector adaptor may be used to provide a better grip when selecting a dose. The release button extension may be used to provide a better grip when giving injections.<br />
<br />
<b>Are the VetPens an accurate way for insulin dosing?</b><br />
The VetPen is ideal for cats and small dogs on low doses of insulin, in which dosing accuracy can be a concern (3,4).
A recent study comparing the precision and accuracy of the VetPen to U40 syringes demonstrated that even when doses were drawn up by trained laboratory technicians, syringes were found to deliver at least 20% to 25% more insulin than needed for a 1-unit dose (5).<br />
<br />
In contrast, VetPen enables doses to be delivered with accuracy and precision down to 0.5 units. In large dogs, dosing accuracy is generally not a problem.<br />
<br />
<b>Do the pens and cartridge need to be refrigerated? Other handling precautions?</b><br />
The VetPen cartridges should be refrigerated (not frozen) and protected from light before opening.<br />
<br />
VetPen does not need to be refrigerated after a cartridge has been started (4), although it probably is best to do so. The loaded VetPen can be stored on its side in the refrigerator.<br />
<br />
VetPen should always be stored or carried with the needle removed and the cap on. To clean the device, wipe with a damp cloth. Do not immerse in water.<br />
<br />
<b>Are the VetPens expensive? How would the costs of the VetPen compare to those associated with the standard insulin vial/syringe method?</b><br />
<br />
The cost of treatment will depend upon the size of the diabetic pet. For smaller dogs and cats, the price of the VetPen with the Vetsulin cartridges and needles will be similar to the cost of the standard 10-mL Vetsulin vial and U-40 insulin syringes. For larger dogs, the standard way of administering Vetsulin (via an insulin syringe) would generally be a more economical way to provide insulin treatment.<br />
<span style="color: red;"><br /></span>
<b><span style="color: red;">Bottom Line:</span></b><br />
<b><span style="color: red;"><br /></span></b>
These insulin pen devices are an alternative to the traditional insulin vial-and-syringe method and offer many advantages. In human diabetic patients, insulin pens have also been found to be less painful than the vial-and-syringe method and are often associated with greater patient preference and social acceptability (6-11). Similar preliminary findings have been documented in dogs and cats (12,13). As a result, this method of insulin delivery may ultimately help to improve glycemic control and should be considered as an alternative insulin delivery method.<br />
<br />
Insulin pens are designed to deliver a fixed insulin dose while insulin syringes rely on the ability of the user to accurately draw up the required insulin dose. One recent study reported that for low doses (below 8 units), the VetPens were more precise and accurate than the insulin syringes (5). In particular, insulin syringes tend to over-deliver, compared to the insulin pen, for very low doses (1 unit). For higher doses (16 units), both devices were comparable (5).<br />
<br />
Similar findings have been reported in human pediatric patients, in which very low doses of insulin must be administered. One older study looked at the reliability of using U100 syringes for accurately administering low doses of insulin in the hospital by pediatric nurses. In that study, attempts to administer doses of 0.5 U or 1.0 U of U-100 insulin resulted in overdosage of 95% and 66%, respectively (14). Based on this study, it's no wonder that small diabetic dogs or cats are often a challenge to regulate when small insulin doses are needed.<br />
<b><br /></b>
<b>References: </b><br />
<ol>
<li>FDA website. <a href="http://www.fda.gov/AnimalVeterinary/NewsEvents/CVMUpdates/ucm389652.htm?source=govdelivery&utm_medium=email&utm_source=govdelivery" target="_blank">FDA Approves First Insulin Product for Use with Automatic Injection Pen in Cats and Dogs</a>.</li>
<li>Press release. <a href="http://www.merck-animal-health-usa.com/news/2014-3-19.aspx" target="_blank">Merck Animal Health Receives FDA Approval of VetPen</a> </li>
<li>Merck Caninsulin website. <a href="http://www.caninsulin.com/vetpen/about-vetpen.asp" target="_blank">Caninsulin® VetPen® helps make pet diabetes management easier </a></li>
<li>Pet Diabetes website. <a href="https://www.abbeyvet-export.co.uk/pdfs/Caninsulin%20Vetpen%20FAQ.pdf" target="_blank">What you need to know about the Caninsulin VetPen</a>. </li>
<li>Burgaud S, Riant S, Piau N. Comparative laboratory evaluation of dose delivery using a veterinary insulin pen. Proceedings World Congress ASAVA/FECAVA/BSAVA 2012;567.</li>
<li>Molife C, Lee LJ, Shi L, et al. <a href="http://www.ncbi.nlm.nih.gov/pubmed/19698067" target="_blank">Assessment of patient-reported outcomes of insulin pen devices versus conventional vial and syringe</a>. Diabetes Technol Ther 2009;11:529-538. </li>
<li>Pearson TL. <a href="http://www.ncbi.nlm.nih.gov/pubmed/20513316" target="_blank">Practical aspects of insulin pen devices</a>. J Diabetes Sci Technol 2010;4:522-531. </li>
<li>Wright BM, Bellone JM, McCoy EK. <a href="http://www.ncbi.nlm.nih.gov/pubmed/22879787" target="_blank">A review of insulin pen devices and use in the elderly diabetic population</a>. Clin Med Insights Endocrinol Diabetes 2010;3:53-63. </li>
<li>Cuddihy RM, Borgman SK. <a href="http://www.ncbi.nlm.nih.gov/pubmed/21768872" target="_blank">Considerations for diabetes: treatment with insulin pen devices</a>. Am J Ther 2013;20:694-702. </li>
<li>Davis EM, Foral PA, Dull RB, et al. <a href="http://www.ncbi.nlm.nih.gov/pubmed/24421496" target="_blank">Review of insulin therapy and pen use in hospitalized patients</a>. Hosp Pharm 2013;48:396-405. </li>
<li>McCoy EK, Wright BM. <a href="http://www.ncbi.nlm.nih.gov/pubmed/20463417" target="_blank">A review of insulin pen devices</a>. Postgrad Med 2010;122:81-88. </li>
<li>Burgaud S, Guillot R, Harnois-Milon G. Clinical evaluation of a veterinary insulin pen in diabetic cats. Proceedings World Congress ASAVA/FECAVA/BSAVA 2012;499.</li>
<li>Burgaud S, Guillot R, Harnois-Milon G. Clinical evaluation of a veterinary insulin pen in diabetic dogs. Proceedings World Congress ASAVA/FECAVA/BSAVA 2012;568.</li>
<li>Casella SJ, Mongilio MK, Plotnick LP, et al. <a href="http://www.ncbi.nlm.nih.gov/pubmed/8502520" target="_blank">Accuracy and precision of low-dose insulin administration</a>. Pediatrics 1993;91:1155-1157. </li>
</ol>
Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com0tag:blogger.com,1999:blog-1407531601642815094.post-78516684920447158832014-03-19T16:11:00.001-04:002014-03-19T16:11:50.136-04:00FDA Approves First Insulin Automatic Injection Pen for Diabetic Dogs and Cats<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjUAHX6PkdRCq3kQJRufTRHStxNMdJz9GZX8vnU-9k36dsVo81b2Os5A1bLRKpeRdIDqAXKICu5ukN50qNNWmSzWUitC2Phu_DyCeCWflo_4xg_X9BHRuRhO4QY4FgVL6nlXkqL-f8P3dc/s1600/Vet+Pen.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjUAHX6PkdRCq3kQJRufTRHStxNMdJz9GZX8vnU-9k36dsVo81b2Os5A1bLRKpeRdIDqAXKICu5ukN50qNNWmSzWUitC2Phu_DyCeCWflo_4xg_X9BHRuRhO4QY4FgVL6nlXkqL-f8P3dc/s1600/Vet+Pen.png" height="282" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><b><span style="font-size: x-small;">VetPen, for use with Vetsulin (in USA) and Caninsulin (outside USA)</span></b></td></tr>
</tbody></table>
The U.S. Food and Drug Administration (FDA) has approved the first insulin injection pen (VetPen, Merck Animal Health) for diabetic cats and dogs, the agency announced today, March 19, 2014 (1).<br />
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<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjlWpOgykKgQK6GvCA5Fd5FuUYuDfLsjyaMy8LcuHD2deaf3wfltSAXceqcGtTPgOZe8QkJkFOzl9xb-bAPIMU36UmXM6mqJtZAx8QLUli7HqrtOEQvIP0lk90lVkrmDefbFd_rqq5ssh0/s1600/VetPen+-+2+sizes.png" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjlWpOgykKgQK6GvCA5Fd5FuUYuDfLsjyaMy8LcuHD2deaf3wfltSAXceqcGtTPgOZe8QkJkFOzl9xb-bAPIMU36UmXM6mqJtZAx8QLUli7HqrtOEQvIP0lk90lVkrmDefbFd_rqq5ssh0/s1600/VetPen+-+2+sizes.png" height="200" width="95" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><b>2 Sizes of VetPens</b></td></tr>
</tbody></table>
The VetPen may now be used to administer Vetsulin insulin cartridges, also made by Merck Animal Health. The refillable VetPen automatically measures the prescribed insulin dose and provides the owners of diabetic dogs and cats with an additional option for insulin delivery.<br />
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There are two sizes of refillable VetPens. One (tan cap) dispenses insulin doses from 1-16 units per dose in full unit increments. The other (blue cap) dispenses 0.5-8 unit doses in full or half unit increments. Both pens use 2.7 ml insulin cartridges which hold a total of 108 units (IU) of U-40 Vetsulin (or Caninsulin). <br />
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Vetsulin is an FDA-approved insulin for use in dogs and cats (2). This insulin is identical to Caninsulin, the brand name of the insulin sold in Europe (3).<br />
<br />
Merck said the VetPen is easier to dose and administer and is more accurate than traditional delivery systems, such as syringes and vials (4). “For years, insulin pens have made managing diabetes more convenient for human diabetics,” the company said. “Merck Animal Health has now brought the same technology to veterinary medicine.”<br />
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An informational website (2) provides tools for both veterinarians and pet owners to make managing pet diabetes easier. More online information about the VetPen can also be found on the Caninsulin website (5); the Pet Diabetes website has an informational brochure that can be downloaded (6).<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi9UudPpxPBNQWBY7SNqj3k5q7fGHttVoss5v85JF5wxNI99m3B7YrCqebqEzgp5J2oHlAVMuWme_3nCjmp_0TdbmIhTB7cQMWNgS_NY-QDovJjPHZfebzYBoic4KOL4Yyo-qZ21gQaWmc/s1600/Administering+insulin+with+vetpen.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi9UudPpxPBNQWBY7SNqj3k5q7fGHttVoss5v85JF5wxNI99m3B7YrCqebqEzgp5J2oHlAVMuWme_3nCjmp_0TdbmIhTB7cQMWNgS_NY-QDovJjPHZfebzYBoic4KOL4Yyo-qZ21gQaWmc/s1600/Administering+insulin+with+vetpen.png" height="212" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><b>Administering insulin to a cat with the VetPen</b></td></tr>
</tbody></table>
For questions on how to obtain Vetsulin or the VetPen, please contact Merck Animal Health Customer Service at 800-521-5767.<br />
<br />
<b>References: </b><br />
<br />
<ol>
<li>FDA website. <a href="http://www.fda.gov/AnimalVeterinary/NewsEvents/CVMUpdates/ucm389652.htm?source=govdelivery&utm_medium=email&utm_source=govdelivery" target="_blank">FDA Approves First Insulin Product for Use with Automatic Injection Pen in Cats and Dogs</a>.</li>
<li>Merck Vetsulin website. <a href="http://www.vetsulin.com/">www.vetsulin.com</a></li>
<li>Merck Caninsulin website. <a href="http://www.caninsulin.com/">www.caninsulin.com</a></li>
<li>Press release. <a href="http://www.merck-animal-health-usa.com/news/2014-3-19.aspx" target="_blank">Merck Animal Health Receives FDA Approval of VetPen</a> </li>
<li>Merck Caninsulin website. <a href="http://www.caninsulin.com/vetpen/about-vetpen.asp" target="_blank">Caninsulin® VetPen® helps make pet diabetes management easier </a></li>
<li>Pet Diabetes website. <a href="https://www.abbeyvet-export.co.uk/pdfs/Caninsulin%20Vetpen%20FAQ.pdf" target="_blank">What you need to know about the Caninsulin VetPen</a>. </li>
</ol>
Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com0tag:blogger.com,1999:blog-1407531601642815094.post-20193588782004735382014-03-12T09:54:00.003-04:002014-03-12T09:54:26.699-04:00What's the Best Insulin for Treating Dogs with Diabetes Mellitus?<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhEZmwZ7pHso3OOuk3bVMFEwZd_-l0jhz5oM3ZukMCVF4YiyMJj1Ne3Z4DqfdNzIGqErmztiVOGhC2OljkI2DSzgoP1ca9RReXSwqUDhx7H_nlmKC2wiMjmPS9EhixjWxvNFjPgwyKV_nY/s1600/weimaraner.png" imageanchor="1" style="clear: left; float: left; margin-bottom: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhEZmwZ7pHso3OOuk3bVMFEwZd_-l0jhz5oM3ZukMCVF4YiyMJj1Ne3Z4DqfdNzIGqErmztiVOGhC2OljkI2DSzgoP1ca9RReXSwqUDhx7H_nlmKC2wiMjmPS9EhixjWxvNFjPgwyKV_nY/s1600/weimaraner.png" /></a><i>I am writing you regarding my 11-year old male Weimaraner, Duke. He has always been in good health but over this past week he has had 2 ”accidents” where he has urinated in the bed. He has also been drinking a lot more water than usual and urinating more too.</i><br />
<i><br /></i>
<i>I took him to the vet because I had a feeling he might be diabetic. My veterinarian confirmed that it was indeed diabetes mellitus and started him on 10 units of NPH, once after breakfast and once after dinner. He has improved since starting the insulin, but remains quite thirsty and continues to urinate excessively.</i><br />
<i><br /></i>
<i>Now I know that this will not give very good control alone because NPH is only a long-acting insulin. I am a Type 1 diabetic, diagnosed when I was 12 years old, so I have quite a bit of experience dealing with this disease. I want my poor puppy to be as controlled as possible so he does not feel like I do when my sugars are out of control— lethargic, nausea, headaches, unquenchable thirst, urinating all the time, and just plain crappy! Not to mention the stress this puts on the on the rest of the body.
</i><br />
<i><br /></i>
<i>If dogs are anything like people, I believe that Duke needs an insulin mixture that will bring his blood glucose down to normal and keep it leveled out. I have been giving him the rapid-acting insulin analog <a href="http://www.humalog.com/Pages/index.aspx" target="_blank">Humalog (insulin lispro)</a> along with the NPH and that seems to be working really well, with marked improvement in his thirst and urination. The only problem is that he needs 4-6 injections of Humalog each day. I was hoping you have had experience with something that would give him the same control as Humalog but with less injections daily.
</i><br />
<i><br /></i>
<i>In the past, I have used short-acting Regular insulin (before Humalog was invented) but I do not remember how the dosing went. I do have much better control with the Humalog but I am also on an insulin pump, so NPH insulin is no longer necessary.</i><br />
<i><br /></i>
<i>Any help you can give to allow my dog Duke better control long term without so many injections would be greatly appreciated.</i><br />
<br />
<b><span style="color: red;">My Response:
</span></b><br />
<br />
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh7jYoIYQ7mWn9LSOoZq9c6lcV5ENOyqJTNbT-pX0WOU4-rc9xdEffcE-MCFDaCBHrCqAmNTUmnaOFBk1SXKFt29b2RS4LA8hpOdfXrfjZBFykJlcTuY88P1yHijr3e55tuNL4mQkayEac/s1600/Vetsulin.png" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh7jYoIYQ7mWn9LSOoZq9c6lcV5ENOyqJTNbT-pX0WOU4-rc9xdEffcE-MCFDaCBHrCqAmNTUmnaOFBk1SXKFt29b2RS4LA8hpOdfXrfjZBFykJlcTuY88P1yHijr3e55tuNL4mQkayEac/s1600/Vetsulin.png" height="200" width="128" /></a>In dogs, veterinarians commonly start with an intermediate-acting insulin (NPH or Vetsulin) twice a day (1,2). In some dogs, I find it necessary to add a short-acting insulin to the longer-acting insulin preparation, but many dogs can achieve adequate glucose control without giving more than 2 injections per day.<br />
<br />
<b>Insulin of choice for canine diabetics</b><br />
In my opinion, the insulin of choice for most dogs is <a href="http://www.vetsulin.com/" target="_blank">Vetsulin</a> (porcine insulin zinc suspension; Merck Animal Health) (3). The main advantage of Vetsulin (known as <a href="http://www.caninsulin.com/" target="_blank">Caninsulin</a> outside the USA (4), is that it is actually composed of both short- and long-acting insulin components (see Figure below, showing the duel peaks of activity) (5,6). So giving Vetsulin is like administrating NPH together with a second, short-acting insulin preparation, like you are doing now. However, Vetsulin works better than NPH for most dogs because it has a longer duration of action than NPH.<br />
<br />
<b>Timing of meals and insulin injection</b><br />
The short-acting amorphous fraction of the Vetsulin, which composes 35% of the insulin activity, acts like regular insulin or Humulog, mainly to control the rise in blood glucose after each meal (6). To help prevent severe rises in glucose after meals, however, it is also important to give the insulin <u>before</u> meals, instead of <u>after</u> the food is ingested, as you are doing now. This protocol will allow the short-acting insulin to be absorbed into the blood stream and ready to act to lower the blood sugar as soon as the food is absorbed from the gastrointestinal tract (7).<br />
<br />
The only time I don't do this insulin-feeding protocol is in dogs that don't always eat their meal well; but even in those dogs, I never wait long after the meal is finished to give the insulin. Instead, I always give the insulin injection as soon as possible, once the dog has eaten a sufficient amount of food.<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjWgFzNs7zMtV2o3PL6wlqfkJx8rvE6zjuxpadK-EWdq3tgMa4jCP43i4_TdGnAUr5MsyrUh1mMY3XqkU70oUCkpSfKMIqG77qBMYHjyFLt8SEtYMR_cQskvIjQb8GcK1Eaon1q2CzgiQY/s1600/Vetsulin.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjWgFzNs7zMtV2o3PL6wlqfkJx8rvE6zjuxpadK-EWdq3tgMa4jCP43i4_TdGnAUr5MsyrUh1mMY3XqkU70oUCkpSfKMIqG77qBMYHjyFLt8SEtYMR_cQskvIjQb8GcK1Eaon1q2CzgiQY/s1600/Vetsulin.jpg" height="261" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><b style="background-color: white; color: #171616; font-family: Verdana, Geneva, sans-serif; font-size: x-small; line-height: 14px; text-align: start;">Vetsulin (porcine insulin zinc suspension), with it's 2 peaks of insulin activity</b></td></tr>
</tbody></table>
<b><br /></b>
<b>References:</b><br />
<br />
<ol>
<li>Nelson RW. Canine diabetes mellitus In: Ettinger SJ, Feldman EC, eds. Textbook of Veterinary Internal Medicine: Diseases of the Dog and Cat. Seventh Edition ed. St. Louis: Saunders Elsevier, 2010;1449-1474.</li>
<li>Davison LJ. Canine diabetes mellitus In: Mooney CT, Peterson ME, eds. BSAVA Manual of Canine and Feline Endocrinology. Fourth ed. Quedgeley, Gloucester: British Small Animal Veterinary Association, 2012;116-132.</li>
<li><a href="http://www.vetsulin.com/" target="_blank">Vetsulin website</a>. www.vetsulin.com </li>
<li><a href="http://www.caninsulin.com/" target="_blank">Caninsulin website</a>. www.caninsulin.com</li>
<li>Monroe WE, Laxton D, Fallin EA, et al. <a href="http://www.ncbi.nlm.nih.gov/pubmed/16231711" target="_blank">Efficacy and safety of a purified porcine insulin zinc suspension for managing diabetes mellitus in dogs</a>. J Vet Intern Med 2005;19:675-682.</li>
<li>Fleeman LM, Rand JS, Morton JM. <a href="http://www.ncbi.nlm.nih.gov/pubmed/19234324" target="_blank">Pharmacokinetics and pharmacodynamics of porcine insulin zinc suspension in eight diabetic dogs</a>. Vet Rec 2009;164:232-237.</li>
<li><span style="font-family: inherit;">Cobry E, McFann K, Messer L, et al. </span><a href="http://www.ncbi.nlm.nih.gov/pubmed/20151766" target="_blank">Timing of meal insulin boluses to achieve optimal postprandial glycemic control in patients with type 1 diabetes</a><span style="font-family: inherit;">. Diabetes Technol Ther 2010;12:173-177. </span></li>
</ol>
Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com30tag:blogger.com,1999:blog-1407531601642815094.post-77654130143286483232014-02-21T11:31:00.001-05:002014-02-21T11:31:08.889-05:00U-40 Insulin Syringes Recalled<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiqE_dauORfhvAPdKpbfBWgS512I_X4nZG3eIhIDK526KLDUvfH66ucILo_AfWpu1E-GhcCS_jdbh_5zvytyXktu1aSNNOTDYZIIf1jEmgcpHaGt46mHJbwfzyTWrsB1iwO7IJ2bljEfm8/s1600/U-40+insulin+syringes.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiqE_dauORfhvAPdKpbfBWgS512I_X4nZG3eIhIDK526KLDUvfH66ucILo_AfWpu1E-GhcCS_jdbh_5zvytyXktu1aSNNOTDYZIIf1jEmgcpHaGt46mHJbwfzyTWrsB1iwO7IJ2bljEfm8/s1600/U-40+insulin+syringes.jpg" height="271" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><h3 style="background-image: none; border-style: none; height: auto; margin: 0px; padding: 0px;">
<span style="font-family: inherit; font-size: x-small;">Med-Vet International Issues Recall of 1/2-cc U-40 Insulin Syringes Due to Mismarked Syringe Barrels (1). </span></h3>
</td></tr>
</tbody></table>
<span style="font-family: inherit;"><br /></span>
<span style="font-family: inherit;">On February 14, 2014 , Med-Vet International initiated a voluntary nationwide recall of 140 boxes of 1/2-cc U-40 insulin syringes (1). The syringes are incorrectly labeled as 40 units per 1/2-cc syringe, whereas they should be marked with only 20 units per 1/2 cc. Obviously, this could potentially result in a lower-than-prescribed dose of insulin being administered, and lead to relapse of signs of diabetes, as well as development of ketoacidosis.</span><br />
<span style="font-family: inherit;"><br /></span>
<span style="font-family: inherit;">Consumers who have these insulin syringes should quarantine all products subject to recall. In addition, if you, as the veterinarian, may have sold these syringes, please inform the clients at once about this product recall so they can change to another insulin syringe.</span><br />
<span style="font-family: inherit;"><br /></span>
<span style="font-family: inherit;">The following 1/2-cc U-40 insulin syringes have been recalled:</span><br />
<ul>
<li><span style="font-family: inherit;">140 boxes of 1/2-cc insulin syringe U-40 with 29g x 1/2” needle. Lot Number: 20120610</span></li>
<li><span style="font-family: inherit;">The product can be identified by Item number: MV1/2CCINS-40 or 1/2CCINS-40 by Oasis.</span></li>
</ul>
<span style="font-family: inherit;">Med-Vet International is arranging for return of all recalled 1/2-cc U-40 insulin syringes. Consumers with questions may contact the company via telephone at (800) 544-7521 or via e-mail at customerservice@shopmedvet.com.</span><br />
<span style="font-family: inherit;"><br /></span>
<b><span style="font-family: inherit;">References:</span></b><br />
<ol>
<li><span style="font-family: inherit;">FDA website (www.fda.gov). <a href="http://www.fda.gov/Safety/Recalls/ucm386613.htm?source=govdelivery&utm_medium=email&utm_source=govdelivery" target="_blank">Med-Vet International Issues Nationwide Recall of Veterinary 1/2cc U-40 Insulin Syringes Due to Mismarked Syringe Barrels</a></span></li>
</ol>
Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com0tag:blogger.com,1999:blog-1407531601642815094.post-54035951360388249092014-02-18T14:36:00.001-05:002014-02-18T14:36:16.740-05:00How to Manage Hyperthyroid Cats that Become Resistant to Methimazole<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjcFbhax5edrx16JLb-fgpSby6IKzCZlBAtB_tD8jFzEFpRLpHGXvp7V-TNv4OhAYVqHeZqxxYpQrOE9N29o7xLiApMI724qVgAqWnYIQpS_RI2os0jG5zV_CnzsI7XGGIFjEMRikcOu9E/s1600/bobo+exam+3+large+lecture.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjcFbhax5edrx16JLb-fgpSby6IKzCZlBAtB_tD8jFzEFpRLpHGXvp7V-TNv4OhAYVqHeZqxxYpQrOE9N29o7xLiApMI724qVgAqWnYIQpS_RI2os0jG5zV_CnzsI7XGGIFjEMRikcOu9E/s1600/bobo+exam+3+large+lecture.jpg" height="265" width="400" /></a></div>
<br />
<i>I have a 19-year old female DSH cat who was diagnosed with hyperthyroidism 5 years ago. I chose not to do the radioactive treatment because that treatment required her being away for several days. I didn't want to do surgery to remove the thyroid gland because she was very weak at the time of the initial diagnosis. </i><br />
<i><br /></i>
<i>Therefore, I have been treating her with methimazole over all these years. Initially, her daily dosage was 5 mg (divided twice daily). Over the years, it has become necessary to increase this first up to 10 mg/day, then to 15 mg (daily doses divided into 2-3 doses per day). This 15-mg dosage was effective at controlling her hyperthyroidism for a short time, but now her serum thyroid value is high again. Because of the persistent hyperthyroidism, many of her clinical signs have returned. She has lost weight, despite the fact that her appetite has increased. I have just increased the methimazole dose up to 10 mg twice a day (20 mg/day) but this still does not appear to be helping. Now I am worried about the effects of the medicine on her kidneys.</i><br />
<i><br /></i>
<i>Do cats just become accustomed to the methimazole and always need an increasing amount? How high can we go with the dosage of the methimazole? </i><br />
<i><br /></i>
<i>Thank you. </i><br />
<br />
<b><span style="color: red;">My Response:
</span></b><br />
<br />
This scenario that you are describing isn't that uncommon in cats treated with methimazole on a long-term basis.
All hyperthyroid cats, as you may know, have one or more thyroid adenomas (benign thyroid tumors), which will continue to grow larger with time (1-7).<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhrd_JXHWxDuthGq0lqiCenvr3c2mZtcIv2XtJNp-3_1fgZJsJ8Dh7nLX0MrO-ANPS4KjPdB2_Cywckeu19QKfB6cZzBtIcsmcBrgZ-mmvM9Gl90VDJXvtPPGmooAEPpXHGskiedmMagC8/s1600/Aa+thyroid+scan+panel+copy.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhrd_JXHWxDuthGq0lqiCenvr3c2mZtcIv2XtJNp-3_1fgZJsJ8Dh7nLX0MrO-ANPS4KjPdB2_Cywckeu19QKfB6cZzBtIcsmcBrgZ-mmvM9Gl90VDJXvtPPGmooAEPpXHGskiedmMagC8/s1600/Aa+thyroid+scan+panel+copy.jpg" height="133" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Thyroid scans of hyperthyroid cats, illustrating that all of these cats will have a thyroid tumor that will continue to grow larger over time. In some cats, these tumors will become very large or huge, which can lead to "resistance" to methimazole.</td></tr>
</tbody></table>
<br />
<b>How methimazole works to control hyperthyroidism</b><br />
Methimazole and other antithyroid drugs work by being taken up by the thyroid tumor where the drugs inhibit thyroid hormone production and secretion (1-4,7). Therefore, most hyperthyroid cats will require higher dosages of methimazole to inhibit thyroid hormone secretion as their goiters become larger and the thyroid tumor volume increases.<br />
<div>
<br /></div>
The methimazole does <u>not</u> change the tumor pathology and cannot stop the tumor from growing (5,6). In some of these cats, the thyroid adenoma also may transform into a thyroid carcinoma as the disease progresses (6,8). Again, methimazole does nothing to the tumor pathology and cannot stop this from happening.<br />
<br />
<b>Why methimazole may become ineffective with time</b><br />
In answer to one of your questions, hyperthyroid cats do not just become <i>accustomed</i> to the methimazole and need an increasing amount. There is a good explanation for the dose increases and why the drug will fail to work in some cats, especially in those treated chronically.<br />
<br />
After use of medical treatment for a number of months to years, many hyperthyroid cats will have fairly large palpable goiters (thyroid enlargement). Because of the large goiter size, these cats can be difficult to regulate and make euthyroid, even when very high daily doses of oral or transdermal methimazole are administered (7). The reason for this is simple— with time, we just can't give a dose of methimazole that is high enough to block thyroid secretion from all of the thyroid tumor cells. In other words, the cat just has too much thyroid tumor tissue and thyroid oversecretion can no longer be adequately suppressed by the methimazole. <br />
<br />
<b>How high can we go with the methimazole dose in this cat?</b><br />
So, what do you do? The dose of methimazole needed to control hyperthyroid cats is based on what it takes to lower the serum T4 concentration into the reference range, so there is not an upper limit to what methimazole dosage can be used. I've gone as high as 30 mg per day in some cats, although the incidence of side effects tends to be higher as you raise the dose (7). So in your cat, I would continue to raise the dose up to 25 mg and then 30 mg/day, as needed. If this fails to completely control the hyperthyroidism, addition of other drugs such as beta-adrenergic blockers (e.g., atenolol) and/or L-carnitine could also be considered (9, 10).<br />
<br />
If your cat was younger, I would strongly recommend definitive therapy (i.e., surgery or radioiodine) in order to remove or destroy the thyroid tumor(s). However, at 19-years of age, that may no longer be feasible, depending on your cat's overall clinical condition.<br />
<br />
<b><span style="color: red;">My Bottom Line:</span></b><br />
The underlying cause of hyperthyroidism in all affected cats is a hyperfunctional thyroid tumor. Unless surgically removed or irradiated with radioiodine, these thyroid tumors will tend to grow larger with time, as the disease progressed. If methimazole is used as initial treatment, the drug may eventually become ineffective, even when higher dosages of the drug are used.<br />
<br />
Overall, I believe that we should be curing the thyroid tumor in the hyperthyroid cat with definitive treatments, not just controlling the hyperthyroid state for the rest of the cat's life with methimazole. In most hyperthyroid cats, especially those that are young to middle-aged, the use of surgical thyroidectomy or radioiodine are, therefore, the treatments of choice. I do not generally recommend using methimazole on a long-term basis, unless we don't believe that the cat will live for another couple of years. Both surgery and radioiodine can be more difficult in cats with large goiters and severe hyperthyroidism, so early definitive therapy is always best. <br />
<b><br /></b>
<b>References:</b><br />
<ol>
<li>Peterson ME. Hyperthyroid diseases In: Ettinger SJ, Feldman EC, eds. Textbook of Veterinary Internal Medicine: Diseases of the Dog and Cat. Fourth ed. Philadelphia: WB Saunders Co, 1995;1466-1487.</li>
<li>Baral R, Peterson ME. Thyroid gland disorders In: Little SE, ed. The
Cat: Clinical Medicine and Management. Philadelphia: Elsevier Saunders,
2012;571-592.</li>
<li>Mooney CT, Peterson ME. Feline hyperthyroidism In: Mooney CT,
Peterson ME, eds. Manual of Canine and Feline Endocrinology Fourth ed.
Quedgeley, Gloucester: British Small Animal Veterinary Association,
2012;199-203.</li>
<li>Peterson ME. Hyperthyroidism in cats In: Rand JS, Behrend E,
Gunn-Moore D, et al., eds. Clinical Endocrinology of Companion Animals.
Ames, Iowa Wiley-Blackwell, 2013;295-310.</li>
<li>Gerber H, Peter H, Ferguson DC, et al. <a href="http://www.ncbi.nlm.nih.gov/pubmed/8053112">Etiopathology of feline toxic nodular goiter.</a> Vet Clin North Am Small Anim Pract 1994;24:541-565. </li>
<li>Peterson M. Hyperthyroidism in cats: <a href="http://www.ncbi.nlm.nih.gov/pubmed/23087006">What's causing this epidemic of thyroid disease and can we prevent it?</a> J Feline Med Surg 2012;14:804-818. </li>
<li>Peterson ME. Treatment of severe, unresponsive, or recurrent
hyperthyroidism in cats. Proceedings of the 2011 ACVIM Forum; 2011 June
15–19; Denver, CO. American College of Veterinary Internal Medicine, pp
104–106.</li>
<li>Peterson ME, Broome MR. <a href="http://www.avmi.net/newfiles/Scintigraphy/SSlinks/293.html" target="_blank">Hyperthyroid cats on long-term medical treatment show a progressive increase in the prevalence of large thyroid tumors, intrathoracic thyroid masses, and suspected thyroid carcinoma</a>. J
Vet Intern Med 2012;26:1523.</li>
<li>Peterson ME. Alternative medical treatments for hyperthyroid cats.
Conference Proceedings North American Veterinary Conference (NAVC)
Conference 2012: Small Animal & Exotics Proceedings 2012;852-858.</li>
<li>Peterson ME. <a href="http://animalendocrine.blogspot.com/2012/09/alternative-medical-treatments-for.html" target="_blank">Alternative Medical Treatments for Hyperthyroid Cats</a>. Animal Endocrine Clinic blog, September 13, 2012.</li>
</ol>
Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com5tag:blogger.com,1999:blog-1407531601642815094.post-52161485285110913112014-02-09T09:42:00.000-05:002014-03-27T17:28:52.224-04:00Managing Addison's Dogs with Concurrent, Uncontrolled Diabetes<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgD3aredZlLAE0no65GUBtaQF95_jb3q-buJ8tvhACY6T2IJzRUWf3UdpyKiMCFm1P3UBhFXh0QJeFVM0iCJxNJf9TGbywVKddeH5e19g5FCZ6eLk584B3K815Hv2KqLI3lE7yFgrOXyak/s1600/Addison's+diabetic+terrier.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgD3aredZlLAE0no65GUBtaQF95_jb3q-buJ8tvhACY6T2IJzRUWf3UdpyKiMCFm1P3UBhFXh0QJeFVM0iCJxNJf9TGbywVKddeH5e19g5FCZ6eLk584B3K815Hv2KqLI3lE7yFgrOXyak/s1600/Addison's+diabetic+terrier.jpg" height="236" width="320" /></a></div>
<br />
<i>I have a 10-year old male Terrier dog named Scooter who now weighs in at 11 pounds (5 kg). He was originally diagnosed diabetes mellitus that we could not get regulated with Vetsulin, even at doses as high as 8 units twice daily. </i><br />
<i><br /></i>
<i>Scooter was subsequently diagnosed with with pituitary-dependent Cushing's disease and was treated with mitotane (Lysodren). Once we got the Cushing's disease under control, his daily insulin requirements fell to 3 units twice a day, and the diabetes was well regulated based on glucose curves done at my vet's hospital.
However, after a few months of treatment with mitotane, it was apparent that Scooter had been severely overdosed with the medicine, which resulted in complete adrenal insufficiency and threw him into a severe Addison's crisis. It was a near death experience for him, but he has pulled threw and is now doing much better off of the mitotane and on treatment for his iatrogenic Addison's disease. </i><br />
<i><br /></i>
<i>Now we have spent the last 3 months trying to stabilize his iatrogenic Addison's disease and concurrent diabetes. Currently, he is on 2.5 mg of fludrocortisone (Florinef) twice day along with 1.25 mg of prednisone twice daily. The Florinef dose has had to be gradually increased to keep his serum electrolytes (sodium and potassium) within their proper ratio and ranges. Based on his last blood test, we may have to increase it yet again, since his serum potassium remains slightly high. </i><br />
<br />
<i>To make matters even worse, his diabetes is now completely out of control, as evidenced by his intense thirst and excessive urinations with heavy amount of glucose in the urine. Serial blood glucose monitored done at my veterinarian's clinic confirms that the blood glucose readings remain very high throughout the day. We have gradually increased the insulin dose back up to 7 units twice daily, but it just doesn't seem to be working</i><i> at all at this point. </i><br />
<br />
<i>What do you recommend that I do? We need to get the Addison's disease controlled but as we have raised the doses of the Florinef and prednisone, Scooter's diabetes is getting worse! </i><i>My vet has suggested that I transition Scooter from the Florinef tablets to Percorten injections in order to stabilize his serum electrolytes. He also told me that the Florinef contains some steroid activity which may be contributing to his high insulin doses. </i><i> Is the steroid in Florinef any less hard on him than the prednisone? </i><br />
<br />
<i>Any advice would be greatly appreciated. </i><br />
<br />
<b><span style="color: red;">My Response: </span></b><br />
<br />
With Scooter, we need to address both his poorly-regulated Addison's disease and his uncontrolled diabetes, as well as the increased thirst (polydipsia) and urination (polyuria). There is a lot going on with Scooter, so let's take one problem at a time.<br />
<br />
<b>Mineralocorticoid replacement: Florinef vs. Percorten-V? </b><br />
For mineralocorticoid replacement for dogs with Addison's disease, either oral fludrocortisone acetate (Florinef) or injectable desoxycorticosterone pivalate (DOCP; Percorten-V) can be used successfully (1-3).<br />
<br />
In your dog, however, I would definitely make the switch to Percorten-V. Some dog's just don't respond very well to treatment with Florinef, and it's not uncommon for dogs to require increasing doses of daily Florinef over time to control the serum electrolyte concentrations (1-3). With high doses of Florinef, this can lead to signs of increased thirst and urination, and may also lead to problems with management of diabetes, as you are seeing in Scooter.<br />
<br />
Since you are having problems controlling the serum electrolytes, I'd recommend starting with the <a href="http://www.percorten.novartis.us/pdf/PercortenV-product-info.pdf" target="_blank">label dose</a> of 2.2 mg/kg, injected every 25-30 days (4). If this drug works to stabilize the serum sodium and potassium levels (and I expect that it will), then we can try to gradually lower the Percorten dosage after a few weeks to months (e.g., I generally try reducing the dose by 10% or so each month). Many dogs will maintain normal serum electrolyte levels on doses between 1-1.5 mg/kg per month, and a few will even need less (1,5).<br />
<br />
<b>Glucocorticoid supplementation in Addison's disease</b><br />
Now let's next turn to your dog's glucocorticoid needs. Dogs with Addison's disease, either spontaneous or iatrogenic (that is, drug-induced, as it was in Scooter), will require replacement glucocorticoids (e.g., prednisone or prednisolone) in addition to the mineralocorticoid supplementation (1-3). Some dogs will do fine without any glucocorticoid supplementation, but the vast majority of dogs will feel better with a small daily dose of glucocorticoid administered daily. Since we know that these dogs cannot secrete normal amounts of cortisol, it certainly makes a great deal of sense to use low-dose glucocorticoid replacement.<br />
<br />
Unfortunately, many dogs with Addison's disease are treated with too much glucocorticoid. Remember that our goal with glucocorticoid supplementation is to provide the same amount of steroid that the dogs would normally produce if their adrenals had not failed.<br />
<br />
For dogs, the daily glucocorticoid maintenance dose for prednisone is only 0.1-0.2 mg/kg/day (3), so that calculates out to only 0.5-1.0 mg per day for Scooter, quite a bit lower that what you are currently giving (2.5 mg per day). That would certainly be enough to cause an increased thirst by itself, but would also contribute to glucocorticoid-induced insulin resistance, making the diabetes uncontrollable despite the higher insulin doses.<br />
<br />
Therefore, we should try to lower the prednisone dosage first down to 1.0 mg once daily (or divided). If he is doing well clinically (i.e., normal appetite and no vomiting), then the dose can be lowered even further, down to 0.5 mg per day. Prednisone or prednisolone are available in 1-mg tablets, as well as an oral solution, making it possible to administer these smaller dosages (6,7).<br />
<br />
<b>Florinef also contains significant glucocorticoid activity</b><br />
In addition to the fact that Addison's dogs are commonly overdosed with prednisone, it's very important to realize that fludrocortisone acetate also possesses moderate glucocorticoid activity, as well as having marked mineralocorticoid potency (2,3). By comparison, fludrocortisone has 10-times the glucocorticoid activity and 125-times the mineralocorticoid activity of cortisol, the glucocorticoid hormone secreted by the adrenal gland. In this regard, fludrocortisone is very different than Percorten-V, which possess no glucocorticoid activity (2,3).<br />
<br />
For the dog with Addison's disease, a glucocorticoid is a glucocorticoid —it makes no difference to Scooter if this glucocorticoid activity comes from prednisone or from the Florinef. This potent glucocorticoid activity of fludrocortisone explains why some dogs will develop polydipsia and polyuria, common side effects associated with higher-dose glucocorticoid treatment in dogs (8). This is another reason why we need to get Scooter off of the Florinef and switch to the Percorten-V.<br />
<br />
<b>Glucocorticoid-induced insulin resistance</b><br />
In all likelihood, the reason for Scooter's poorly controlled diabetes is related to insulin resistance associated with glucocorticoid excess (9,10). By stopping the Florinef and providing mineralocorticoid replacement with Percorten-V instead, we will remove one source of excess glucocorticoid. Lowering his daily prednisone dose will also help.<br />
<br />
As we remove the cause of the insulin resistance, the dose of insulin will again fall. You should monitor Scooter closely during this period to ensure that insulin overdosage and hypoglycemia do not occur, and lower the insulin dose as needed.<br />
<br />
<b>Don't forget to rule out urinary tract infections</b><br />
Finally, don't forget that diabetic dogs, no matter what the cause, will commonly develop urinary tract infections. Think about it: a bladder full of sugar-laden urine is a perfect breeding ground for bacteria to thrive! Such urinary tract infections will also commonly contribute to insulin resistance (9,10) but can also lead to kidney failure, if the infection ascends from the bladder up to the kidneys.<br />
<br />
For this reason, I always recommend checking a complete urinalysis and urine culture in all dogs (and cats) with insulin resistance. However, even if the diabetes is well-controlled, I still recommend doing a urinalysis with culture twice yearly in all of my diabetic patients.<br />
<b><br /></b>
<b>References: </b><br />
<ol>
<li>Kintzer PP, Peterson ME. <a href="http://www.ncbi.nlm.nih.gov/pubmed/9127289" target="_blank">Treatment and long-term follow-up of 205 dogs with hypoadrenocorticism</a>. J Vet Intern Med 1997;11:43-49. </li>
<li>Church DB. Canine hypoadrenocorticism In: Mooney CT, Peterson ME, eds. BSAVA Manual of Canine and Feline Endocrinology. Fourth ed. Quedgeley, Gloucester: British Small Animal Veterinary Association, 2012;156-166.</li>
<li>Kintzer PP, Peterson ME. Canine hypoadrenocorticism In: Bonagura JD, Twedt DC, eds. Kirk's Current Veterinary Therapy, Volume XV. Philadelphia: Saunders Elsevier, 201<span style="font-family: inherit;">4;
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<li>Lynn RC, Feldman EC, Nelson RW. <a href="http://www.ncbi.nlm.nih.gov/pubmed/8440628" target="_blank">Efficacy of microcrystalline desoxycorticosterone pivalate for treatment of hypoadrenocorticism in dogs. DOCP Clinical Study Group</a>. J Am Vet Med Assoc 1993;202:392-396. </li>
<li>Bates JA, Shott S, Schall WD. <a href="http://www.ncbi.nlm.nih.gov/pubmed/23438457" target="_blank">Lower initial dose desoxycorticosterone pivalate for treatment of canine primary hypoadrenocorticism</a>. Aust Vet J 2013;91:77-82. </li>
<li>Peterson ME: <a href="http://animalendocrine.blogspot.com/2013/12/treating-small-breed-addisons-dogs-with.html" target="_blank">Treating small-breed Addison's dogs with low doses of prednisone or prednisolone</a>. Animal Endocrine Clinic blog, December 14, 2013. </li>
<li>Plumb, DC. Plumb's Veterinary Drug Handbook. Seventh Edition, Wiley-Blackwell. 2011.</li>
<li>Melián C, M. Pérez-Alenza, D, Peterson ME. Hyperadrenocorticism in dogs, In: Ettinger SJ (ed): Textbook of Veterinary Internal Medicine: Diseases of the Dog and Cat (Seventh Edition). Philadelphia, Saunders Elsevier, 2010;1816-1840.</li>
<li>Hess RS. <a href="http://www.ncbi.nlm.nih.gov/pubmed/20219491" target="_blank">Insulin resistance in dogs</a>. Vet Clin North Am Small Anim Pract 2010;40:309-316. </li>
<li>Peterson ME. <a href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=7660542" target="_blank">Diagnosis and management of insulin resistance in dogs and cats with diabetes mellitus.</a> Vet Clin North Am Small Anim Pract 1995;25:691-713. </li>
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Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com9tag:blogger.com,1999:blog-1407531601642815094.post-51276479513796087132014-01-31T05:01:00.000-05:002014-01-31T05:01:14.700-05:00What's the Expected Time for Signs of Feline Hyperthyroidism to Resolve after Treatment?<div class="separator" style="clear: both; text-align: center;">
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<i>My 16-year old cat was recently treated with radioiodine (I-131) for his severe hyperthyroidism. How long after radioiodine treatment will the thyroid values normalize and the symptoms of the hyperactive thyroid begin to resolve so he feels better? </i><br />
<i><br /></i>
<i>My cat lost about half of his body weight, much of it in muscle mass. Will his wasted muscles ever return to normal? If so, when can I expect to see improvement?</i><br />
<br />
<span style="color: red;"><b>My Response:</b> </span><br />
<br />
You have asked two good questions, which, on the surface seem simple enough to answer. The answers to "how long for clinical signs to resolve" however, depend on a number of factors. I'll do my best to explain why it's not possible for me to give you the definitive answers you want. <br />
<br />
<b>How long does it take for serum thyroid hormone levels to normalize after I-131?</b><br />
Depending on the dosing protocol used, about 90% of cats will have serum thyroid hormone concentrations (e.g., T4 and T3) within reference range limits by 30 days after I-131 treatment. Most of the remaining cats will show a nice drop in T4 and T3 levels when rechecked in a month, but it will take longer to for their thyroid hormone concentrations to completely normalize.<br />
<br />
In general, the full extent of the radioiodine treatment will be evident by 3 months after treatment, although a few cats continue to show even more (minor) improvement when rechecked at 4 to 6 months.<br />
<br />
As the thyroid values normalize, the clinical signs we see also gradually resolve. Some signs, such as nervousness or rapid heart rate, generally resolve fairly quickly, whereas other signs, such as marked weight loss and muscle wasting, obviously take much longer.<br />
<br />
<b>How fast do we <i>want</i> the serum thyroid values to fall after radioiodine treatment?</b><br />
My goal in treating hyperthyroid cats with radioiodine is to <u>gradually</u> normalize the high serum thyroid hormone concentrations— not lower the values too quickly. I'd rather that the thyroid values fall slowly over the first month after treatment, allowing the rest of the body to gradually get used to being euthyroid once again. This is especially true in cats with concurrent kidney disease, when a drastic fall in thyroid values can aggravate the serum kidney values and can even lead to severe renal failure.<br />
<br />
To achieve this gradual fall in the high serum thyroid hormone levels, I administer the smallest dose necessary to cure the hyperthyroidism. By giving individualized, lower doses of radioiodine, we can also reduce the incidence of post-treatment hypothyroidism (underactive thyroid condition) in these cats.<br />
<b><br /></b>
<b>How often does the radioiodine fail to cure the hyperthyroidism?</b><br />
About 5% of cats that I treat will remain slightly hyperthyroid at the 3-month follow-up period. Many treatment facilities will claim a higher rate of cure (98-100%) than I do, which is made possible by administering higher doses of radioiodine to their cats. In addition to decreasing the incidence of persistent hyperthyroidism, the use of higher radioiodine doses will also hasten the rate of decline in the serum thyroid hormone concentrations.<br />
<br />
So why not use this high-dose I-131 protocol instead of my lower-dose approach? Simple — the downside of administering higher radioiodine doses is that this method will lead to a higher rate of iatrogenic hypothyroidism as both the thyroid tumor, as well as most normal thyroid tissue, are irradiated and destroyed (1,2). As I've previously discussed (see my post, <a href="http://animalendocrine.blogspot.com/2013/04/estimating-radioiodine-dose-to.html" target="_blank"><i>Estimating the Radioiodine Dose to Administer to Cats with Hyperthyroidism</i></a>), more that 30% of cats will become hypothyroid using the standard high-dose treatment protocol, but this incidence could in fact be much higher, possibly up to 75%.<br />
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<b>Diagnosing iatrogenic hypothyroidism</b><br />
To monitor for iatrogenic hypothyroidism, we routinely run a serum thyroid panel (i.e., total T4, T3, free T4, and TSH) at 1 and 3 months after treatment (2,3). Most facilities recommend monitoring just the total T4 concentration, but this is not adequate for monitoring since many hypothyroid cats will maintain a low-normal total T4 value, despite being hypothyroid. Based on our studies, it's becoming increasing clear that feline hypothyroidism can only be diagnosed by finding low to low-normal T4 and T3 values in conjunction with high TSH values.<br />
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<b>Restoring lost body weight and muscle mass</b><br />
Once euthyroidism is reestablished, most cats will gain weight within a few weeks (certainly by 2-3 months). If marked muscle wasting has occurred, it may not be possible to completely regain the lost muscle. Remember that it will help to feed a diet that's higher in protein (40-50% of calories), higher in fat (40-50% of calories), and relatively low in carbs (less than 15% of calories) (4). For more information, check out my post on <i><a href="http://endocrinevet.blogspot.com/2011/09/best-diet-to-feed-hyperthyroid-cats.html" target="_blank">The Best Diet to Feed Hyperthyroid Cats</a>.</i><br />
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<b>References:</b><br />
<div class="p1">
</div>
<ol>
<li><span style="font-family: inherit;">Peterson ME, Broome MR. Radioiodine for feline hyperthyroidism In: Bonagura JD, Twedt DC, eds. </span><span style="font-family: inherit;">Kirk's Current Veterinary Therapy, Volume XV</span><span style="font-family: inherit;">. Philadelphia: Saunders Elsevier, 2014.</span></li>
<li><span style="font-family: inherit;">Peterson ME. Feline focus: <a href="http://www.ncbi.nlm.nih.gov/pubmed/23975586" target="_blank">Diagnostic testing for feline thyroid disease: hypothyroidism</a>. </span><span style="font-family: inherit;">Compend Contin Educ Vet</span><span style="font-family: inherit;"> 2013;35:E4. </span></li>
<li><span style="font-family: inherit;">Peterson ME. Diagnosis and management of iatrogenic hypothyroidism In: Little SE, ed. </span><span style="font-family: inherit;">August's Consultations in Feline Internal Medicine</span><span style="font-family: inherit;">: Elsevier, 2014;in press.</span></li>
<li><span style="font-family: inherit;">Peterson ME. Nutritional management of endocrine disease in cats. Proceedings of the Royal Canin Feline Medicine Symposium 2013;23-28.</span></li>
</ol>
<br />
<b>Related Blog Posts:</b><br />
<ul>
<li>Peterson ME. <a href="http://endocrinevet.blogspot.com/2012/07/how-does-radioiodine-really-work-to.html" target="_blank">How Does Radioiodine Really Work to Treat Hyperthyroidism?</a> Insights into Veterinary Endocrinology blog. July 12, 2012.</li>
<li>Peterson MEL <a href="http://animalendocrine.blogspot.com/2013/04/estimating-radioiodine-dose-to.html" target="_blank">Estimating the Radioiodine Dose to Administer to Cats with Hyperthyroidism</a>. Animal Endocrine Clinic blog. April 30, 2013.</li>
<li>Peterson ME. <a href="http://animalendocrine.blogspot.com/2013/05/success-rates-for-radioiodine-treatment.html" target="_blank">Success Rates for Radioiodine Treatment in Hyperthyroid Cats</a>. Animal Endocrine Clinic blog. May 24, 2013.</li>
<li>Peterson ME. <a href="http://endocrinevet.blogspot.com/2011/09/best-diet-to-feed-hyperthyroid-cats.html" target="_blank">The Best Diet to Feed Hyperthyroid Cats</a>. Insights into Veterinary Endocrinology blog. September 13, 2011</li>
</ul>
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Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com6tag:blogger.com,1999:blog-1407531601642815094.post-75881259467535822132014-01-21T16:50:00.000-05:002014-01-21T16:50:03.012-05:00Combining Rapid and Long-Acting Insulin Analogs for Dogs with Diabetes <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiggV2wmD9mC0aslFnXG9Ufq3d_B-QKkeg_TKmez_mr4p5cMtJp_X6FZPbkXQdHUncEFdRjAL9A330KHHvWtnQRT_CQ9BZa0PzcKtD3os6CetIUrQPjLPMXTgi9ckSOT5UBHSZMjYh3jgM/s1600/Diabetic+Poodle.jpg" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiggV2wmD9mC0aslFnXG9Ufq3d_B-QKkeg_TKmez_mr4p5cMtJp_X6FZPbkXQdHUncEFdRjAL9A330KHHvWtnQRT_CQ9BZa0PzcKtD3os6CetIUrQPjLPMXTgi9ckSOT5UBHSZMjYh3jgM/s1600/Diabetic+Poodle.jpg" /></a><i>I am the owner of Coco, a 6-year old male Poodle who has been diagnosed with diabetes mellitus. I noticed the symptoms myself, as I too am a Type 1 diabetic (I was diagnosed 42 years ago at the age of 7 years).
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<i>My dog's blood sugar was slightly more than 400 mg/dl when I brought him in for testing. That’s terribly high. I am a man with deep concern about this disease, and I personally keep myself in very good control (my A1-C tests are always in the 6’s). And thus, I am interested in having excellent control of my dogs health too. </i><br />
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<i>I’ve been directed by my veterinarian to give ”Coco” 2 daily injections of long-acting type insulin (I give him glargine (Lantus) since that’s what I use for my diabetes). So I started him 5 units of Lantus twice a day but still found him to be drinking far too much water and still having high sugar levels. So, I then added in small amounts of insulin lispro (<a href="http://www.humalog.com/Pages/index.aspx" target="_blank">Humalog</a>) to better control his sugar. I’ve not yet taken him back in for spot checking of his blood, but I do notice the Humalog is helping decrease his water drinking and urinating at normal levels. So now, I give him 2 shots at breakfast and 2 at dinner—5 units of Humalog and 10 units of Lantus twice per day. And I watch him closely but find he is doing well. I see no signs of low blood sugar. </i><br />
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<i>Do you find my plan a good one? Am I overreacting by giving him Humalog in addition to the Lantus? I’m not a doctor, but I think a blood sugar curve should be between 70-150 mg/dl to keep him healthy, just like in human diabetic patients. Is this correct? Is there something better I can do? </i><br />
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<i>Finally, is there a simpler way to give the injections? I use a small needled Pen for his injections between his shoulders in a pinch of skin. Is there a needle-free ”Jet” type injection system that would be better than the needles? </i><br />
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<i>Thank you very much for any help advice you can share. </i><br />
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<b>My Response: </b><br />
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Although insulin glargine (Lantus) can be used to treat diabetic dogs (1-3), it doesn't always work well as the sole insulin preparation, as you have discovered in your dog. Therefore, I don't usually start with glargine in dogs, but I use either NPH (<a href="http://www.humulin.com/Pages/index.aspx" target="_blank">Humulin</a>) or lente (<a href="http://www.vetsulin.com/" target="_blank">Vetsulin</a>) insulins, which give us a higher success rate (4,5).<br />
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Your approach to combining a long-acting insulin analog (glargine; Lantus) with a rapid-acting analog (lispro; Humalog) is certainly an acceptable one. Insulin lispro has been proven to be effective in dogs (6) and combing Lantus with Humalog has been recommended as an option by some investigators (1). If you use Lantus and Humalog yourself, this may be a good option for you. The rapid-acting Hunalog insulin will lower the blood sugar rise that occurs after meals, whereas the longer-acting Lantus will act as a background insulin to maintain glucose levels between meals.<br />
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You mention that you would like keep your dog's blood sugar well-controlled. That is a good idea, especially if you want to prevent the formation of diabetic cataracts, which are common in dogs with diabetes (7,8). However, to do that, the use of "spot checks" of his blood glucose concentration will not be enough. You are going to have to do periodic blood glucose curves, either done at home or in the hospital (9-11).
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<br />
Finally, our current options for insulin injections are either use of an insulin needle and syringe or an insulin pen, such as the <a href="http://www.lantus.com/hcp/about-lantus/pen-at-glance.aspx" target="_blank">Lantus SoloStar pen</a> (12).Use of needle-free, jet injector for insulin delivery has been reported (13,14). However, to my knowledge, such jet injectors are not yet available commercially, and they certainly have not been tested in diabetic dogs. <br />
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<b>
References:</b><br />
<ol>
<li>Mori A, Sako T, Lee P, et al. <a href="http://www.ncbi.nlm.nih.gov/pubmed/18575956" target="_blank">Comparison of time-action profiles of insulin glargine and NPH insulin in normal and diabetic dogs</a>. Vet Res Commun 2008; 32:563-573. </li>
<li>Fracassi F, Boretti FS, Sieber-Ruckstuhl NS, et al. <a href="http://www.ncbi.nlm.nih.gov/pubmed/22008227" target="_blank">Use of insulin glargine in dogs with diabetes mellitus</a>. Vet Rec 2012;170(2):52.</li>
<li>Peterson ME. <a href="http://endocrinevet.blogspot.com/2012/04/treating-diabetic-dogs-with-insulin.html" target="_blank">Treating diabetic dogs with insulin glargine</a>. Blog post. May 3, 2012.</li>
<li>Palm CA, Boston RC, Refsal KR, et al. <a href="http://www.ncbi.nlm.nih.gov/pubmed/19175720" target="_blank">An investigation of the action of neutral protamine Hagedorn human analogue insulin in dogs with naturally occurring diabetes mellitus</a>. J Vet Intern Med 2009;23:50–55. </li>
<li>Monroe WE, Laxton D, Fallin EA, et al. <a href="http://www.ncbi.nlm.nih.gov/pubmed/16231711" target="_blank">Efficacy and safety of a purified porcine insulin zinc suspension for managing diabetes mellitus in dogs</a>. J Vet Intern Med 2005;19:675-82.</li>
<li>Sears KW, Drobatz KJ, Hess RS. <a href="http://www.ncbi.nlm.nih.gov/pubmed/22390184" target="_blank">Use of lispro insulin for treatment of diabetic ketoacidosis in dogs</a>. J Vet Emerg Crit Care (San Antonio) 2012;22:211-218. </li>
<li>Beam S, Correa MT, Davidson MG. <a href="http://www.ncbi.nlm.nih.gov/pubmed/11397260" target="_blank">A retrospective-cohort study on the development of cataracts in dogs with diabetes mellitus: 200 cases</a>. Vet Ophthalmol 1999;2:169-172. </li>
<li>Wilkie DA, Gemensky-Metzler AJ, Colitz CM, et al. <a href="http://www.ncbi.nlm.nih.gov/pubmed/16939461" target="_blank">Canine cataracts, diabetes mellitus and spontaneous lens capsule rupture: a retrospective study of 18 dogs</a>. Vet Ophthalmol 2006;9:328-334. </li>
<li>Wiedmeyer CE, DeClue AE. <a href="http://www.ncbi.nlm.nih.gov/pubmed/21295721" target="_blank">Glucose monitoring in diabetic dogs and cats: adapting new technology for home and hospital care</a>. Clin Lab Med 2011;31:41-50. </li>
<li>Cook AK. <a href="http://www.ncbi.nlm.nih.gov/pubmed/22768878" target="_blank">Monitoring methods for dogs and cats with diabetes mellitus</a>. J Diabetes Sci Technol 2012;6:491-495.</li>
<li>Davison LJ. Canine diabetes mellitus In: Mooney CT, Peterson ME, eds. BSAVA Manual of Canine and Feline Endocrinology. Fourth ed. Quedgeley, Gloucester: British Small Animal Veterinary Association, 2012;116-132.</li>
<li>Association AD. <a href="http://www.ncbi.nlm.nih.gov/pubmed/11679469" target="_blank">Insulin administration</a>. Diabetes Care 2001;24:1984-1987. </li>
<li>Engwerda EE, Abbink EJ, Tack CJ, et al. <a href="http://www.ncbi.nlm.nih.gov/pubmed/21715522" target="_blank">Improved pharmacokinetic and pharmacodynamic profile of rapid-acting insulin using needle-free jet injection technology</a>. Diabetes Care 2011;34:1804-1808. </li>
<li>Engwerda EE, Tack CJ, de Galan BE. <a href="http://www.ncbi.nlm.nih.gov/pubmed/24089542" target="_blank">Needle-free jet injection of rapid-acting insulin improves early postprandial glucose control in patients with diabetes</a>. Diabetes Care 2013;36:3436-3441. </li>
</ol>
Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com1tag:blogger.com,1999:blog-1407531601642815094.post-23432379815531163432014-01-13T11:24:00.001-05:002014-01-13T11:24:28.045-05:00What's the Human Risk Associated with Handling of Thyroid Medications?<div class="separator" style="clear: both; text-align: center;">
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<i>Maybe I am missing something here, but I have a question about the human risk associated with handling thyroid medications. Why do you state that owners should be careful when handling and cutting methimazole tablets (Tapazole of Felimazole) because of the human safety concerns (1,2), when I can find no mention that we should use any precautions when handling or cutting L-thyroxine (L-T4) tablets? I've heard that we should wear gloves when handling methimazole tablets or applying methimazole transdermally to the cat's ear, but no one has ever mentioned the need for gloves with L-T4 tablets.</i><br />
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<i>So why is handling L-thyroxine any less of a concern than handling methimazole? Do they not both have the same potential to affect human thyroid levels? If handling methimazole can lower a human's thyroid levels, why wouldn't handling an L-thyroxine preparation potentially lead to hyperthyroidism?</i><br />
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<b>My Response: </b><br />
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Methimazole and L-thyroxine are totally different drugs, with different patterns of absorption and metabolism. Methimazole is a potent antithyroid drug whereas L-thyroxine is a synthetic form of natural thyroid hormone.<br />
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<b>Methimazole</b><br />
As you state, we must be careful when cutting methimazole tablets or applying transdermal methimazole since either form of methimazole could potentially be absorbed via human skin (1,2). Methimazole is a human teratogen (i.e., the drug may cause birth defects) and crosses the placenta concentrating in the fetal thyroid gland. Besides being a safety issue in pregnant women or women who may become pregnant, the drug should not be handled by lactating women because methimazole is transferred in breast milk at a high rate.<br />
<br />
The same precautions pertain regardless of what methimazole product is used, i.e., the veterinary brand-name Felimazole preparation or a human brand-name or generic product. The methimazole tablets should not be cut with our bare hands. We want to wash our hands after administering the medication to minimize skin and oral contamination; repeated and chronic exposure could pose a risk.<br />
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<b>L-Thyroxine</b><br />
As compared to methimazole, L-thyroxine is not absorbed well from the skin. Results of two studies found that the hormone is not absorbed into the systemic circulation to have an effect on all tissues of the body (3,4). In support of that, of the few dogs that I have evaluated on transdermal L-T4, none have responded to the transdermal replacement therapy with a rise in serum T4 concentrations (5). I know that some compounded pharmacies will sell transdermal preparations of L-T4 but I do not believe that they actually work. Ask for some actual data and you will get none!<br />
<br />
So go ahead and cut all the L-T4 pills that you want. It will not get absorbed unless you ingest the hormone supplement so you should still wash your hands to remove any residual L-T4 residue from your hands.<br />
<br />
<b>References:</b><br />
<ol>
<li>Peterson ME. <a href="http://animalendocrine.blogspot.com/2012/09/methimazole-handling-precautions-for.html" target="_blank">Methimazole-Handling Precautions for Cat Owners</a>. Blog post, Animal Endocrine Clinic, September 2, 2012.</li>
<li>Felimazole-Coated Tablets. <a href="http://www.dechra-us.com/files/dechraUSA/downloads/Product%20inserts/Felimazole.pdf" target="_blank">Product insert</a>. Available at: www.dechra-us.com/files/dechraUSA/downloads/Product%20inserts/Felimazole.pdf </li>
<li>Padula C, Pappani A, Santi P. <a href="http://www.ncbi.nlm.nih.gov/pubmed/17931806" target="_blank">In vitro permeation of levothyroxine across the skin</a>. Int J Pharm 2008 12;349:161-165. </li>
<li>Padula C, Nicoli S, Santi P. <a href="http://www.ncbi.nlm.nih.gov/pubmed/19162148" target="_blank">Innovative formulations for the delivery of levothyroxine to the skin</a>. Int J Pharm 2009;372:12-16.</li>
<li>Peterson ME. <a href="http://endocrinevet.blogspot.com/2012/03/alternative-dosage-forms-of-l-thyroxine.html" target="_blank">Alternative Dosage Forms of L-Thyroxine for Hypothyroid Dogs</a>. Blog post, Insights into Veterinary Endocrinology, March 28, 2012.</li>
</ol>
Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com0tag:blogger.com,1999:blog-1407531601642815094.post-4824299395012948842013-12-31T10:58:00.000-05:002013-12-31T10:58:59.807-05:00A Tribute to a Special Patient, "The Colonel"<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiLK-dMdDWmUFyBS-hP4nxQDkc124CLnFY4nStiujcAGSUqhkmBl1tbUdqfny1XiYoEHBPV2-jhbbYCvJOU3tvzaeG4ZabC9FBfdGGEP6LOQmrvc3Tvu-PGf3l99S_v4u1Ad1owAsPBBm8/s1600/The+Colonel.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="400" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiLK-dMdDWmUFyBS-hP4nxQDkc124CLnFY4nStiujcAGSUqhkmBl1tbUdqfny1XiYoEHBPV2-jhbbYCvJOU3tvzaeG4ZabC9FBfdGGEP6LOQmrvc3Tvu-PGf3l99S_v4u1Ad1owAsPBBm8/s400/The+Colonel.jpg" width="357" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">The Colonel after his radioiodine treatment</td></tr>
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<span style="font-family: inherit;"><br /></span>
<span style="font-family: inherit;"><i>The Colonel was one of our favorite hyperthyroid patients at the Animal Endocrine Clinic. We first met him over two years ago, when he was referred to us for severe and uncontrolled hyperthyroidism.</i></span><br />
<span style="font-family: inherit;"><i>His thyroid tumor was huge and resistant to treatment, necessitating a large dose of radioiodine to cure him. </i></span><br />
<span style="font-family: inherit;"><i><br /></i></span>
<span style="font-family: inherit;"><i>The Colonel ended up staying with us for a long time after treatment since the owner has small children in the house, but none of us minded; we all loved having this wonderful cat at our practice! He had a </i></span><i>super personality and enjoyed each day with a zest for life.</i><i style="font-family: inherit;"> </i><br />
<span style="font-family: inherit;"><i><br /></i></span>
<span style="font-family: inherit;"><i>He later when on to develop hypothyroidism, which we successfully managed with daily thyroid hormone replacement therapy. Unfortunately, he later went on to develop cancer of he urinary bladder, which lead to urinary obstruction and worsening of his kidney failure.</i></span><br />
<span style="font-family: inherit;"><i><br /></i></span>
<i><span style="font-family: inherit;">The Colonel's owner wrote this tribute in memory of him. This cat poem puts into words, so </span>beautifully<span style="font-family: inherit;">, what we all feel when we lose one of our best friends. I wanted to share it with all of you so you can get a sense of how special this cat really was to all of us. </span></i><br />
<span style="font-family: inherit;"><i><br /></i></span>
<span style="font-family: inherit;"><i>However, I must warn you — you will likely cry as you read this touching <span style="background-color: white; line-height: 19.1875px;">epitaph</span>, as we do everytime we reread it. </i></span><br />
<span style="font-family: inherit;"><i><br /></i></span>
<i><span style="font-family: inherit;">We all loved this cat.</span></i> <i><span style="font-family: inherit;">He </span>truly<span style="font-family: inherit;"> will be missed.</span></i><br />
<i style="font-family: inherit;"><br /></i><i style="font-family: inherit;">Dr. Mark Peterson and Staff at the Animal Endocrine Clinic</i><br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgKIL0-Ii5hyphenhyphenNCHodWP4wteiis8cTubTF99eX4M-L1JPIwbDGJUWieJIv-OVyDlTIRq45EyoyGg73Um1iYbgLLYgYUdGcl6N3NkPFoz7zxonQKP_CgHbjWB7c4l-XICWpG_LKj0gBtwRSI/s1600/The+Colonel+2.JPG" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="400" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgKIL0-Ii5hyphenhyphenNCHodWP4wteiis8cTubTF99eX4M-L1JPIwbDGJUWieJIv-OVyDlTIRq45EyoyGg73Um1iYbgLLYgYUdGcl6N3NkPFoz7zxonQKP_CgHbjWB7c4l-XICWpG_LKj0gBtwRSI/s400/The+Colonel+2.JPG" width="365" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Watching the gerbils during his long boarding period at the hospital</td></tr>
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<br />
<br />
<div style="text-align: center;">
<i><b><span style="font-size: large;">GONE </span></b></i></div>
<div style="text-align: center;">
<i><b>by Beverly Cole </b></i></div>
<div style="text-align: center;">
<br /></div>
I don't have to close the bedroom doors, no longer worried your nails will wreak havoc on the rugs.<br />
<br />
I am cleaning up the last kernel of your Lord forsaken litter, a battle that I waged for years, that I have finally won. A pyrrhic victory.<br />
<br />
I am picking off fur from my sweater without my usual grumbling. The fur will appear less and less now, the couch clean, no tufts of orange and white randomly floating through the air.<br />
<br />
There's no more food to order for you. No more subcutaneous fluids to stave off kidney failure. No more thyroid medication. No heartburn relief pills.<br />
<br />
We fought for you as hard as you fought for yourself. No, you fought even harder. You loved your life with a passion experienced by few, as simple and serene as it was.<br />
<br />
I am taking your fleece blanket out of the dryer. Your urine stains now replaced by my salty tears.<br />
<br />
You were just a cat. A 4-year-old flunky mouser who wound up at a shelter. At your best—16 pounds of pomp and circumstance and brilliance and at your worst — a shrunken shell of what was, desperately clinging to life despite the pain.<br />
<br />
I haven't told the kids yet, just saying you're at the doctor when they asked me where you are. The little one calls to you in her small voice, then says "maybe he's in his room and you forgot," she says. No, dearest, I haven't forgotten where he is. When I close my eyes, I see you on the cold steel table, now lifeless, yet still filled with your impenetrable dignity although your eyes are now sunken and still.
<br />
<br />
I am packing up your brush, the same brush we bought when we started together, 13 years ago. When I groomed you the first time, you meowed and yawned at the same time, rolling onto your back, bored and happy, then gently nipped my hand to remind me who was in charge, a devilish glint in your eyes. When I brushed you this last time, you barely moved your head, so I stopped, not wanting to cause you more pain.<br />
<br />
Your fur wasn't always urine soaked. Your smell wasn't always unbearable. That was only recently, after the cancer in your bladder had obstructed your ability to urinate, after the kidney failure had taken over. Before that you were impeccable. Meticulously grooming until your fur shone.<br />
<br />
I still hear your cry—strong and plaintive, demanding, not the crusty, faltering mew you have been able to muster recently.<br />
<br />
It is hard to be in this house without you. My stomach feels void when I realize that the small crackle I hear is not your footsteps coming upstairs to say goodnight to the kids. I stop myself when I enter the house, almost hearing my voice greet you hello, as I have for the last 13 years. You're not here to answer or come over. You'll never be here again.<br />
<br />
I see a ghost of you on the couch waiting for me to sit down at night. I am trying to decide what's more devastating—reliving your death every moment I re-realize you're not here, or knowing that I will get used to your absence.<br />
<br />
You were just a cat. You were mine. And I miss you so. My dear, dear friend.<br />
<br />
You were my best friend, many times my sole ally, and you trusted me with your life. I hope it was a good one.
<br />
<br />
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<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj2v7-JP50CwYeg3eK7bIw5gguKQVgdvpqUg0Vm-J8wSMEBgUNOhldMptlk5PlzTl5RgG9i2EM-7P_6ofzwPyb_90lRGo35iP0vz65EWYJOiFw5QBUHs8J_G_sCqcjnozwEVdROWm8brOs/s1600/The+Colonel3+.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="277" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj2v7-JP50CwYeg3eK7bIw5gguKQVgdvpqUg0Vm-J8wSMEBgUNOhldMptlk5PlzTl5RgG9i2EM-7P_6ofzwPyb_90lRGo35iP0vz65EWYJOiFw5QBUHs8J_G_sCqcjnozwEVdROWm8brOs/s400/The+Colonel3+.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">The Colonel (1997-2013)</td></tr>
</tbody></table>
<br />Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com4tag:blogger.com,1999:blog-1407531601642815094.post-74104466509854107382013-12-24T10:05:00.000-05:002013-12-24T10:05:05.435-05:00Can Methimazole Cause Anemia in Hyperthyroid Cats?<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjHvkRTAo2nrrcP8j0CYVmwIH3yrjgIIKjRRugoHEf1cTy2greKNH38TliiXbYbp_tmc-tPJx-GmtXiwe8RPMHmx-3zFqs1ZX8CezvjQL1DqKScPJtZgPVRnF8FT8zdv_U4ASLudH5Uw1w/s1600/Missy+again.jpg" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" height="200" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjHvkRTAo2nrrcP8j0CYVmwIH3yrjgIIKjRRugoHEf1cTy2greKNH38TliiXbYbp_tmc-tPJx-GmtXiwe8RPMHmx-3zFqs1ZX8CezvjQL1DqKScPJtZgPVRnF8FT8zdv_U4ASLudH5Uw1w/s200/Missy+again.jpg" width="145" /></a></div>
<i>I am very concerned about my 14-year old male DSH cat. He was diagnosed in the spring with hyperthyroidism and has been treated with oral methimazole (Tapazole). </i><br />
<i><br /></i><i> After the first 6 months of treatment, I brought him back to my vet because I was concerned about how skinny he was (very little weight gain on the medication). The vet tested him and increased the Tapazole dosage. He said not to be concerned unless he continued to lose weight.</i><br />
<i><br /></i><i>Now, 2 months later, my cat's weight has held steady on the increased dose of methimazole, but he still remained so skinny that I brought him back for another recheck— even though he wasn't losing weight. It turned out he has developed anemia, so severe that he needed a blood transfusion. He had a bone marrow biopsy, which was consistent with a regenerative anemia. Now my vet wants to just wait and redo his CBC to see how he is in another week.</i><br />
<i><br /></i><i>Because we aren't sure if the methimazole caused the anemia, he isn't putting him back on it right now. He recommended trying Hill's y/d. I tried it (just one can), but my cat isn't keen on it (won't eat it), and he is skinnier than ever now so I don't have the luxury of giving it a chance — I don't want to risk him starving to death!</i><br />
<i><br /></i><i>Now that he's been off the methimazole for about a month. I am really worried about him because he's lost even more weight.</i><br />
<i><br /></i><i>My questions include the following:</i><br />
<ol>
<li><i>Can a cat with anemia or recovering from anemia still be a candidate for radioiodine treatment?</i></li>
<li><i>Can a severely underweight cat be treated for radioiodine treatment? He's only 5 pounds now!</i></li>
<li><i>If my cat has been off of the methimazole for a month, how much time do we have to get him treated again for his hyperthyroidism? Do we need to restart the methimazole before we do the radioiodine treatment? I'm worried he'll die before I can get it properly addressed. </i></li>
<li><i>If I do go for the radioiodine treatment, will he have to wait for a period of time to be treated, since he's eaten a bit of y/d?</i></li>
</ol>
<i>Thank you so much!</i><br />
<br />
<b>My Response:</b><br />
<br />
Sorry to hear that your cat isn't doing well. Although rare, antithyroid drugs, including methimazole, can produce hematologic abnormalities, including hemolytic anemia in cats (1-5). If the drug is responsible for the anemia in your cat, it should never be restarted because that would be life-threatening.<br />
<br />
Even if we forget about the anemia for a moment, it is certainly clear that methimazole has not been an effective treatment in your cat. Feeding a low-iodine diet (y/d) might help if he would eat it (many cats won't) but that too is less likely to be successful in cats with severe, chronic, or advanced hyperthyroidism.<br />
<br />
Treatment with radioiodine would probably the best treatment, but we would need to be certain that the anemia is resolving before moving forward with this treatment. Anemia is a sign, not a diagnosis in itself. If the methimazole isn't causing it, we need to figure out what is responsible, since that is a sign of serious disease. The good news is that if it is regenerative, that suggests that the bone marrow will be able to respond once the insulting factor (e.g., methimazole) has been removed. Nonregenerative, aplastic anemia is a rare but very serious complication of methimazole treatment in man (5,6), which has only been reported in 1 cat (7); let's hope that this is not the case in your cat.<br />
<br />
If the anemia resolves and doesn't recur now that your cat is off the methimazole, I would strongly consider the radioiodine treatment. To do that treatment, we do NOT need to pretreat a cat with methimazole; in fact, we like to have owners stop the drug 1-2 weeks prior to I-131 treatment. Feeding a small amount of y/d will not interfere with the treatment. And finally, severely underweight cats with hyperthyroidism certainly can be treated with radioiodine. Since it's likely that your cat's thyroid tumor may be larger than the average hyperthyroid cat, a larger dose of radioiodine might be needed.<br />
<br />
<b>References:</b><br />
<ol>
<li>Peterson ME, Hurvitz AI, Leib MS, et al. <a href="http://www.ncbi.nlm.nih.gov/pubmed/6609915" target="_blank">Propylthiouracil-associated hemolytic anemia, thrombocytopenia, and antinuclear antibodies in cats with hyperthyroidism</a>. J Am Vet Med Assoc 1984;184:806-808. </li>
<li>Peterson ME, Kintzer PP, Hurvitz AI. <a href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=3265728" target="_blank">Methimazole treatment of 262 cats with hyperthyroidism</a>. J Vet Intern Med 1988;2:150-157. </li>
<li>Baral R, Peterson ME. Thyroid gland disorders In: Little SE, ed. The Cat: Clinical Medicine and Management. Philadelphia: Elsevier Saunders, 2012;571-592.</li>
<li>Peterson ME. Hyperthyroid diseases In: Ettinger SJ, Feldman EC, eds. Textbook of Veterinary Internal Medicine: Diseases of the Dog and Cat. Fourth ed. Philadelphia: WB Saunders Co, 1995;1466-1487.</li>
<li>Yamamoto A, Katayama Y, Tomiyama K, et al. <a href="http://www.ncbi.nlm.nih.gov/pubmed/15072706" target="_blank">Methimazole-induced aplastic anemia caused by hypocellular bone marrow with plasmacytosis</a>. Thyroid 2004;14:231-235. </li>
<li>Edell SL, Bartuska DG. <a href="http://www.ncbi.nlm.nih.gov/pubmed/171299" target="_blank">Aplastic anemia secondary to methimazole-case report and review of hematologic side effects.</a> J Am Med Womens Assoc 1975;30:412-413. </li>
<li>Weiss DJ. <a href="http://www.ncbi.nlm.nih.gov/pubmed/16434225" target="_blank">Aplastic anemia in cats - clinicopathological features and associated disease conditions 1996-2004.</a> J Feline Med Surg 2006;8:203-206. </li>
<li>Peterson ME, Broome MR. Radioiodine for feline hyperthyroidism In: Bonagura JD, Twedt DC, eds. Kirk's Current Veterinary Therapy, Volume XV. Philadelphia: Saunders Elsevier, 2014 (in press).</li>
</ol>
Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com4tag:blogger.com,1999:blog-1407531601642815094.post-16133359425953288382013-12-17T08:58:00.000-05:002013-12-17T08:58:57.992-05:00Using a Low-Iodine Diet (y/d) in Hyperthyroid Cats Allowed Outdoors<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj5se5IR3RAzwflyz2f2vIg6zhpqM8y48n8tfIMgvy0rVJ0VKhaimfl9zbY4vEkT7BxGfHUldXO8ELQFycv6VSd8Vpfbm6dQ9xPVfLMA7hUsTj2tuc2FKEyoUIKuETR2sXz36Ve6ueB7nQ/s1600/tomechipmunk+copy.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj5se5IR3RAzwflyz2f2vIg6zhpqM8y48n8tfIMgvy0rVJ0VKhaimfl9zbY4vEkT7BxGfHUldXO8ELQFycv6VSd8Vpfbm6dQ9xPVfLMA7hUsTj2tuc2FKEyoUIKuETR2sXz36Ve6ueB7nQ/s400/tomechipmunk+copy.jpg" height="400" width="340" /></a></div>
<i><br /></i>
<i>Is feeding the low-iodine diet (Hill's y/d) an appropriate or reasonable choice for a hyperthyroid cat that is allowed outside and hunts? </i><br />
<br />
<i>Will the diet work to control the hyperthyroid state if the cat eats small prey?</i><br />
<br />
<b>My Response</b>:
<br />
<br />
No, Hill's y/d would not work to lower the high serum T4 and T3 in a cat in this situation.<br />
<br />
All species (cattle, pigs, chickens, birds, mice and other rodents) all contain iodine in their muscle tissue (1,2). Iodine may be ingested in the diet as a supplement, but it's also present in soil, which ends up in the plants ruminants and other animals may eat (3,4).
Remember that iodine is an essential nutrient and is needed by all animals (including humans!).<br />
<br />
This cat, by eating birds and rodents (not eating an iodine deficient diet, of course), would ingest too much iodine for the y/d to be effective. To lower T4 secretion, the diet has to be very, very low in iodine.<br />
<b><br /></b>
<b>References:</b><br />
<ol>
<li>Hemken RW. <a href="http://www.ncbi.nlm.nih.gov/pubmed/383673" target="_blank">Factors that influence the iodine content of milk and meat: a review</a>. Journal of Animal Science 1979;48:981-985. </li>
<li>Downer JV, Hemken RW, Fox JD, et al. <a href="http://www.ncbi.nlm.nih.gov/pubmed/7275866" target="_blank">Effect of dietary iodine on tissue iodine content in the bovine</a>. Journal of Animal Science 1981;52:413-417. </li>
<li>Whitehead DC. <a href="http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2389.1973.tb00763.x/abstract" target="_blank">Studies on iodine in British soils</a>. Journal of Soil Science 1973;24:260-270. </li>
<li>Fuge R, Johnson CC. <a href="http://www.springerlink.com/content/r8x702u7g6317353/" target="_blank">The geochemistry of iodine — a review</a>. Environmental Geochemistry and Health 1986;8:31-54.</li>
</ol>
Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com0tag:blogger.com,1999:blog-1407531601642815094.post-74241195392192890332013-12-14T08:58:00.000-05:002013-12-15T14:41:56.636-05:00Treating Small-Breed Addison's Dogs with Low Doses of Prednisone or Prednisolone<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhZtAKUZ8iWvc0wvgHAKzLidLW2qLl-XP9UInkjLC8oBSHFw3UCKsNVz5eaDwOtm8Ig1EMtmVCrWuTjYHlubiy09EeQgCwerYVXbP-zJP8e55WBnjusgiQEsLnAFuK-XJUqedUqfF6hGCk/s1600/Toy+Poodle.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhZtAKUZ8iWvc0wvgHAKzLidLW2qLl-XP9UInkjLC8oBSHFw3UCKsNVz5eaDwOtm8Ig1EMtmVCrWuTjYHlubiy09EeQgCwerYVXbP-zJP8e55WBnjusgiQEsLnAFuK-XJUqedUqfF6hGCk/s1600/Toy+Poodle.jpg" height="303" width="320" /></a></div>
<br />
My 4-year old Toy Poodle was diagnosed with atypical Addison's disease about 6 weeks ago. She weighs 11.8 lbs and is taking 1.25 mg of prednisolone per day. She is not receiving any mineralocorticoid supplementation (i.e., Florinef or Percortin-V) for now since her serum sodium and potassium levels are in the normal range. We will continue to monitor that because we know that that might change and mineralocorticoids will have to be added to her treatment.<br />
<br />
For her glucocorticoid needs, we are using a 5-mg tablet of prednisolone that we cut into quarters to administer a 1.25-mg dose each day. This is extremely tricky, and there is probably never a day that she gets an exact dose because the tablets do not cut without some crumbling.<br />
<br />
So I have two main questions:<br />
<ol>
<li>First, my dog has developed a ravenous appetite and finishes her meals very quickly. Normally, she has a picky appetite. I know that you generally recommend giving these dogs a much lower dosage, and that a lower dosage would be better for her overall health since she will be on this daily dosage for the rest of her life. Should her prednisolone dosage be lowered to help with the appetite issue? </li>
<li>Second, is there any other tablet or form of prednisolone that would be easier for us to administer to her so that she gets the proper amount each day? The 5-mg tablet just isn't working very well for us. </li>
</ol>
Thank you for your help.<br />
<br />
<b>My Response:</b><br />
<br />
The glucocorticoid replacement dose I use for prednisone or prednisolone in dogs with Addison's disease is 0.1-0.2 mg/kg/day. So at 11.8 pounds (5.4 kg), that calculates out to be only 0.5 mg/day, up to a maximum dose of 1.0 mg/day. So if you are giving your small dog 1.25 mg/day, that means you are giving too much of the drug. That would certainly be enough to induce iatrogenic Cushing's disease, as reflected by the increased appetite.<br />
<br />
In dogs, prednisone is converted to prednisolone within the body. So basically, these two glucocorticoids can be used interchangeably.<br />
<br />
I would try to lower the daily prednisone/prednisolone dose down to 0.5 mg each day. Administrating too much glucocorticoid will cause increased hunger (as you see in your dog). Overdosage of prednisone, prednisolone or any other glucocorticoid can also lead to lethargy, weight gain, enlargement of the abdomen, muscle atrophy, and muscle weakness. Decreasing the dose of the prednisone or prednisolone should help prevent any of these problems.<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEigEBvGgrwQc6ZY9oIE5-mXb3bb8Qmy6RROnIZD6J_o8Jb_HxodbJJ8nsgXjY8l7-3bR8zCq7CrBYfmLs7pT9lEZ5ZHSNhMIkFLiTUzh9oN6T-JxK3kh3d0lWWZq65_JfG9Qr-YNaVj78g/s1600/Prednisone+1-mg+tablet.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEigEBvGgrwQc6ZY9oIE5-mXb3bb8Qmy6RROnIZD6J_o8Jb_HxodbJJ8nsgXjY8l7-3bR8zCq7CrBYfmLs7pT9lEZ5ZHSNhMIkFLiTUzh9oN6T-JxK3kh3d0lWWZq65_JfG9Qr-YNaVj78g/s1600/Prednisone+1-mg+tablet.jpg" height="200" width="200" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><b>Fig. 1: Prednisone is available as a 1-mg tablet</b></td></tr>
</tbody></table>
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhYg5xWaSJUb6qFzvYnvbDH6aggDpeqxiPNTiRST8A0F3ukUZYWY2WfYc8c_cM8Qjx982_fFKDzGMyJneIv-kdk8QUc8sW6HUi0s2Zq1NfZyXfyG57-E9q1ySz28-TbGtSLHau-kwbi4Dc/s1600/Prednisolone+solution.jpg" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhYg5xWaSJUb6qFzvYnvbDH6aggDpeqxiPNTiRST8A0F3ukUZYWY2WfYc8c_cM8Qjx982_fFKDzGMyJneIv-kdk8QUc8sW6HUi0s2Zq1NfZyXfyG57-E9q1ySz28-TbGtSLHau-kwbi4Dc/s1600/Prednisolone+solution.jpg" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><b>Fig 2: Prediapred</b>Oral prednisolone<br />
liquid (1 mg/mL) </td></tr>
</tbody></table>
Prednisone tablets are available as 1-mg and 2.5-mg sizes, which can be helpful in dosing small to medium-sized dogs (Figure 1).<br />
<br />
In addition, both prednisone and prednisolone are available as a syrup/oral liquid or solution, available as a 1 mg/mL concentration (Figure 2). Examples of liquid prednisolone products include <span style="font-family: inherit;"><span style="background-color: white; color: #222222;">Pediapred</span><span style="background-color: white; color: #222222;"><span style="font-size: x-small;">®</span> (Celltech Pharm); </span><span style="background-color: white; color: #222222;">Millipred</span><span style="background-color: white; color: #222222;"><span style="font-size: x-small;">®</span> (Laser); </span><span style="background-color: white; color: #222222;">Orapred</span><span style="background-color: white; color: #222222;"><span style="font-size: x-small;">®</span> (Sciele); </span><span style="background-color: white; color: #222222;">Veripred</span><span style="background-color: white; color: #222222;"><span style="font-size: x-small;">®</span> </span><span style="background-color: white; color: #222222;">20</span><span style="background-color: white; color: #222222;"> </span><span style="background-color: white; color: #222222;">Hawthorn); and </span><span style="background-color: white; color: #222222;">Flo-Pred</span><span style="background-color: white; color: #222222;"><span style="font-size: x-small;">®</span> (Taro). <span style="font-family: inherit;">For prednisone,</span></span><span style="background-color: white; color: #222222;"> Intensol</span><span style="background-color: white; color: #222222;"><span style="font-size: x-small;">®</span> </span><span style="background-color: white; color: #222222;">Concentrate</span><span style="background-color: white; color: #222222;"> (Roxane) oral solution is available.</span></span><br />
<br />
All of these formulations are human-labeled products so your veterinarian may not be familiar with them. Your local pharmacy will know about them, however.<br />
<br />
Either way, I'd get either the 1-mg tablets and give half a tablet a day. Or use a liquid formulation (1 mg/mL) and give 0.5 mg (1/2 mL per day).<br />
<br />
<b>References:</b><br />
<ol>
<li><span style="font-family: inherit;">Plumb, DC. Plumb's Veterinary Drug Handbook. Seventh Edition, </span><span style="font-family: inherit;">Wiley-Blackwell. 2011.</span></li>
</ol>
Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com3tag:blogger.com,1999:blog-1407531601642815094.post-8005107169784038392013-11-22T11:31:00.002-05:002013-11-22T11:33:08.040-05:00Difficult Swallowing in Cats with Hyperthyroidism<div class="separator" style="clear: both; text-align: center;">
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We have a 13-year old male cat named Balki with hyperthyroidism and moderate renal disease. He has a history of diabetes, but that has been in remission for the latter for several months.<br />
<br />
Balki's main problem at the moment is trouble eating. My veterinarian just puts it down to the renal disease. However, it seems he wants to eat, but has difficulty swallowing. It has progressively gotten worse, to the point where he is now barely eating.<br />
<br />
He also has had several episodes of reverse sneezing. When trying to eat, he extends his neck and gulps, then turns away from the food being offered. He also sometimes drools, and often spits out the food. He has most difficulty with dry food.<br />
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Can you give any advice on what might be causing this, and what tests he might need to find out, and how to help him to be able to eat?<br />
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<b>My Response:</b><br />
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The typical hyperthyroid cat eats well (usually an increased appetite). These cats almost never develop anorexia, and difficulty swallowing (dysphagia) never occurs as a direct result of hyperthyroidism (1-4).<br />
<br />
Most cats with moderate to severe renal disease will develop a decreased appetite as a result of their uremia, but they don't show signs of dysphagia (5).
Most likely, your cat has disease either in the caudal pharygeal (throat) region or esophagus that is causing some obstruction to the food eaten (6-10). With the history of reverse sneezing, I'd say the problem is most likely in the caudal pharynx.<br />
<br />
I'd recommend starting with a good oral examination (under sedation) to look for a lesion or mass in the pharygeal area. If nothing is seen, then endoscopy may be needed. Radiography or other imaging (e.g., CT scan) may also be required to help define the extent of your cat's disease (9-11).<br />
<br />
Could thyroid tumors ever grow large enough to compress the esophagus and produce signs of dysphagia? That would be extremely unlikely, since even cats with large thyroid carcinomas almost always continue to eat well and don't have any problems swallowing. However, I have had two cats in my career that had thyroid carcinoma which invaded the esophagus, leading to signs of esophagitis and esophageal obstruction. In any case, the chance of that being the problem in your cat would be about 1 in a million; again, that would best be diagnosed with endoscopy and CT imaging.<br />
<br />
<b>References:</b><br />
<ol>
<li>Baral R, Peterson ME. Thyroid gland disorders In: Little SE, ed. The
Cat: Clinical Medicine and Management. Philadelphia: Elsevier Saunders,
2012;571-592.</li>
<li>Mooney CT, Peterson ME. Feline hyperthyroidism In: Mooney CT,
Peterson ME, eds. Manual of Canine and Feline Endocrinology Fourth ed.
Quedgeley, Gloucester: British Small Animal Veterinary Association,
2012;199-203.</li>
<li>Peterson ME. Hyperthyroidism in cats In: Rand JS, Behrend E,
Gunn-Moore D, et al., eds. Clinical Endocrinology of Companion Animals.
Ames, Iowa Wiley-Blackwell, 2013;295-310.</li>
<li>Peterson ME. <a href="http://animalendocrine.blogspot.com/2011/05/top-10-signs-of-hyperthyroidism-in-cats.html" target="_blank">Top 10 signs of hyperthyroidism in cats</a>. Animal Endocrine Clinic blog post. March 21, 2011.</li>
<li>DiBartola SP, Rutgers HC, Zack PM, et al. <a href="http://www.ncbi.nlm.nih.gov/pubmed/3583899" target="_blank">Clinicopathologic findings associated with chronic renal disease in cats: 74 cases (1973-1984)</a>. J Am Vet Med Assoc 1987;190:1196-1202. </li>
<li>Watrous BJ. <a href="http://www.ncbi.nlm.nih.gov/pubmed/6359652" target="_blank">Clinical presentation and diagnosis of dysphagia</a>. Vet Clin North Am Small Anim Pract 1983;13:437-459. </li>
<li>Vos JH, van der Gaag I. <a href="http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0442.1987.tb00300.x/abstract" target="_blank">Canine and feline oral-pharyngeal tumours</a>. Zentralbl Veterinarmed A 1987;34:420-427.</li>
<li>Mattson A. <a href="http://www.ncbi.nlm.nih.gov/pubmed/7817488" target="_blank">Pharyngeal disorders</a>. Vet Clin North Am Small Anim Pract 1994;24:825-854. </li>
<li>Gengler W. Gagging. In: Ettinger SJ, Feldman EC, eds.The Textbook of Veterinary Internal Medicine. St Louis, Mo, USA: Saunders Elsevier; 2010:189–191. </li>
<li>Jergens AE. Diseases of the esophagus. In: Ettinger SJ, Feldman EC, eds. The Textbook of Veterinary Internal Medicine. St Louis, Mo, USA: Saunders Elsevier; 2010:1487–1499. </li>
<li> Pollard RE. I<a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3671744/" target="_blank">maging evaluation of dogs and cats with dysphagia</a>. ISRN Vet Sci 2012;2012:238505. </li>
</ol>
Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com4tag:blogger.com,1999:blog-1407531601642815094.post-73990112550687662942013-11-02T11:27:00.001-04:002013-11-02T11:27:40.289-04:00Review of the BSAVA Manual of Canine and Feline Endocrinology, 4th EditionThe BSAVA Manual of Canine and Feline Endocrinology, coedited by Drs. Carmel Mooney and Mark Peterson, received a favorable review by Dr. Krista Visser ‘t Hooft in the November issue of the Journal of Small Animal Practice.<br />
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<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="http://onlinelibrary.wiley.com/store/10.1111/jsap.12090/asset/jsap12090.pdf?v=1&t=hnj00t2q&s=a6b0ad2556b9638cbe24a9236e69e71242fcb7ce" imageanchor="1" style="margin-left: 1em; margin-right: 1em;" target="_blank"><img border="0" height="640" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg7bMyqrhqSQa-fX2ZYOUsdnnl6O25gwNikwDWV_y1ovwbf2ShoQf-eZQDaaRu2q45VbnmT18lJN-1FRr9UgYuKN5Gr2J3Kgzodco_7YeQe6O9EAcnTMB6eMcn3CpzeuWSIkKN_BuiwRj4/s640/Book+Review+BSAVA+Manual+of+Canine+and+Feline+Endocrinology.jpg" width="464" /></a></div>
<br />
This review can be downloaded by <a href="http://onlinelibrary.wiley.com/store/10.1111/jsap.12090/asset/jsap12090.pdf?v=1&t=hnj00t2q&s=a6b0ad2556b9638cbe24a9236e69e71242fcb7ce" target="_blank">clicking on this link</a>.Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com0tag:blogger.com,1999:blog-1407531601642815094.post-54490457439294237262013-10-26T22:52:00.000-04:002013-10-26T22:52:24.409-04:00Can a Special Diet be Formulated to Treat Hyperthyroidism in Cats?<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjemeOX6eUEbQDzFhcLjRPTCFI3VNFI1YPAOA__CWcjJPjZDaMy4xs2wYq0YMGf4LRu_NhyphenhyphenZwlm4sEiOt9o8ivzRAZOYB9Z9-Y2nQdzczgu8BgcqKqqYwxDTyccreoxi7hkcxFvfauqA5I/s1600/Hyperthyroid+cat+cleaning.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="368" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjemeOX6eUEbQDzFhcLjRPTCFI3VNFI1YPAOA__CWcjJPjZDaMy4xs2wYq0YMGf4LRu_NhyphenhyphenZwlm4sEiOt9o8ivzRAZOYB9Z9-Y2nQdzczgu8BgcqKqqYwxDTyccreoxi7hkcxFvfauqA5I/s400/Hyperthyroid+cat+cleaning.jpg" width="400" /></a></div>
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<i>I have a 13-year old female DSH cat that has recently been diagnosed with hyperthyroidism. Unfortunately found out that she is severely allergic to methimazole (severe vomiting and anorexia), so I cannot treat her with medication (even though I've read this medicine can cause other health issues).</i><br />
<i><br /></i>
<i>My next option was to feed her the Hill's y/d diet, but she absolutely refuses to eat that food. I then began an online search to see if I could make my own low-sodium cat food that would mimic the Hill's diet. My online research brought me to your blogs about hyperthyroidism and diet.</i><br />
<i><br /></i>
<i>After reading many of your blogs, I found where you say that a high protein/low carb diet is beneficial to the hyperthyroid cat (<a href="http://endocrinevet.blogspot.com/2011/09/best-diet-to-feed-hyperthyroid-cats.html">http://endocrinevet.blogspot.com/2011/09/best-diet-to-feed-hyperthyroid-cats.html</a>), but it doesn't address sodium content.</i><br />
<i><br /></i>
<i>Do you believe a diet referenced in your blog would be a life-long treatment for a cat with hyperthyroidism? Or should I pay a veterinary nutritionist to compose a diet for my cat with an iodine level at or below 0.32 ppm (<a href="http://www.2ndchance.info/lowIodine.htm">www.2ndchance.info/lowIodine.htm</a>), which Hill's y/d diet allows? I recently called the nutritionists at UC Davis about such a diet, but was told that they have never made a diet for hyperthyroidism in cats.</i><br />
<i><br /></i>
<i>I've also read that too low of sodium in a cat's diet will cause the thyroid to once again over-produce hormones to compensate. To say the least, I'm confused. I'm at a crossroad wondering if I should try a diet or go ahead and have the I-131 treatment done for my cat. </i><br />
<i><br /></i>
<i>Thank you so much for your opinion and response.</i><br />
<br />
<b><span style="color: red;">My Response:</span></b><br />
<br />
<b>High protein, low-carbohydrate diet for hyperthyroid cats</b><br />
First of all, my recommendation to feed hyperthyroid cats a diet higher in protein and lower in carbohydrates is based on what we know about the secondary complications of hyperthyroidism.<br />
<br />
Hyperthyroidism is a hypermetabolic, catabolic state. Therefore, in hyperthyroidism, the body may be forced to use it's own muscle tissue to supply increased energy it needs. Because of these increased protein needs of the hyperthyroid cats, loss of lean body mass and muscle wasting is common. By adding more protein to the diet, this will help preserve or restore lost muscle mass, but feeding a high protein diet, by itself, will do nothing to lower thyroid hormone secretion or correct hyperthyroidism.<br />
<br />
My recommendation for feeding hyperthyroid cats a low-carb diet is based on the fact that hyperthyroid cats commonly develop a form of prediabetes. Feeding a lower carb diet will help prevent the onset of overt diabetes in these cats. Even if this was not true, cats have absolutely no dietary requirement for carbohydrate and cats in the wild would normally ingest only 1-2% of their daily calories in the form of carbs (1). But again, limiting the amount of carbohydrates in a hyperthyroid cat's diet would do nothing to treat the hyperthyroid condition.<br />
<br />
Overall, a diet higher in protein and lower in carbs, is actually a more "natural" diet for cats (1,2). But this natural diet fed to hyperthyroid cats must be combined with another treatment directed specially at the thyroid gland (e.g., antithyroid drugs, surgical thyroidectomy, or radioiodine).<br />
<b><br /></b>
<b>Salt and the thyroid</b><br />
In cats, both sodium and chloride (i.e., salt) are required in relatively small amounts in the diet. Nutritional requirements for dietary salt in cats are available from regulation associations or scientific councils, mostly based on studies establishing sodium requirements in cats (3,4). Salt restriction has been historically advocated for cats in some disease states (mainly cardiovascular and kidney diseases) (5,6). No study has confirmed the benefit of such dietary intervention in cats.<br />
<br />
However, feeding a cat a low sodium (or salt) diet will not do anything to lower thyroid hormone secretion from the thyroid gland. In other words, we have no evidence at all that a low salt diet can be used as a treatment for hyperthyroidism. Now, because iodine is commonly added to salt as a treatment for iodine deficiency (7,8), using a lower salt diet could lower iodine levels very slightly.<br />
<br />
<b>Iodine and the thyroid</b><br />
The y/d diet made by Hill's (named, Prescription Diet y/d Feline –Thyroid Health) is an iodine deficient diet (9-11). Unlike sodium or chloride, iodine is one of the essential building blocks needed for thyroid hormone synthesis.<br />
<br />
<div>
<span class="Apple-style-span" style="color: #0000ee;"><span class="Apple-style-span" style="color: black;">The main thyroid hormones secreted by the feline thyroid include thyroxine (T4) and triiodothyronine (T3). If we look at the thyroxine molecule, it contains four atoms of iodine per
molecule, and that's how the </span></span>common abbreviation<span class="Apple-style-span" style="color: #0000ee;"><span class="Apple-style-span" style="color: black;"> "T4" was derived. Triiodothyronine contains one less iodine atom, thus the
common abbreviation "T3." Therefore, it's the number of iodine atoms in
each of these thyroid hormones that determines the "number"</span></span> in T4 or T3.</div>
<div>
</div>
<br />
<div>
The basis for using a severely restricted iodine diet to treat
hyperthyroid cats is that iodine is an essential component of both T4
and T3. With severe dietary iodine deficiency, the thyroid cannot
produce adequate amounts of thyroid hormone (8,9).<br />
<br />
Hill's y/d is clearly an iodine deficient diet, containing levels of
approximately 0.2 mg/kg (0.2 ppm) on a dry matter basis, well below the
minimum daily requirement for adult cats (0.46 mg/kg or 0.46 ppm) of
food (9-11). Our current data does indicate that feeding y/d, a diet severely
restricted to overtly deficient in iodine, will result in normalization
of T4 levels in most hyperthyroid cats. Since iodine is an essential nutrient and has other functions other than making T4 and T3 (12), the long-term effects of such iodine deficiency in cats remains unclear.</div>
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<br /></div>
<b>Can a low-iodine home-made diet be formulated?</b><br />
<div>
I am well aware of the claim by some, including <a href="http://%28www.2ndchance.info/lowIodine.htm)" target="_blank">Dr. Hines</a>, that it is possible to make your own low-iodine diet. However, if this were true, then why would we ever feed the Hill's y/d diet, which is very unnatural? </div>
<div>
<br /></div>
<div>
You can certainly talk to a veterinary nutritionist about making an iodine-deficient diet for your cat (13). Unfortunately, it is just not that easy to formulate such a diet, and I do not know of anyone who has made one. That's especially true if we want to feed a higher protein, lower-carbohydrate diet (iodine is present is most meat, since iodine is a required nutrient in all animals, including cattle, chickens, and pigs). And remember, cats are meant to eat a low-carb, high-protein diet!</div>
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<br /></div>
<div>
<b><span style="color: red;">My Bottom Line:</span></b><br />
<b><span style="color: red;"><br /></span></b></div>
<div>
At 13-years of age (a middle-aged senior cat), I would consider a definitive form of treatment of the hyperthyroidism to be ideal. I'd talk to your veterinarian about the possibility of the use of radioiodine or surgical thyroidectomy. Once your cat is cured, then we can concentrate on the use of nutrition to help restore any lost muscle mass and to improve glucose metabolism.</div>
<div>
<br />
<b>References:</b><br />
<ol>
<li>Eisert R. <a href="http://www.ncbi.nlm.nih.gov/pubmed/21088842" target="_blank">Hypercarnivory and the brain: protein requirements of cats reconsidered</a>. J Comp Physiol B 2011;181:1-17.</li>
<li>Zoran DL. <a href="http://www.ncbi.nlm.nih.gov/pubmed/12479324" target="_blank">The carnivore connection to nutrition in cats</a>. Journal of the American Veterinary Medical Association 2002;221:1559-1567.</li>
<li>AAFCO (Association of American Feed Control Officials). Official Publication, 2007. </li>
<li>NRC (National Research Council). Minerals. In: Nutrient Requirements of Dogs and Cats. Washington DC, The National Academy Press, 2006:145-192. </li>
<li>Xu H, Laflamme DP, Long GL. <a href="http://www.ncbi.nlm.nih.gov/pubmed/19073369" target="_blank">Effects of dietary sodium chloride on health parameters in mature cats</a>. J Feline Med Surg 2009;11:435-441. </li>
<li>Reynolds B. Dietary salt and cats: evidence-based approach. Proceedings of the 21st ECVIM-CA Congress, 2011.</li>
<li>Zimmermann MB. <a href="http://www.ncbi.nlm.nih.gov/pubmed/19460960" target="_blank">Iodine deficiency</a>. Endocr Rev 2009;30:376-408. </li>
<li>Zimmermann MB, Andersson M. <a href="http://www.ncbi.nlm.nih.gov/pubmed/23035804" target="_blank">Assessment of iodine nutrition in populations: past, present, and future</a>. Nutr Rev 2012;70:553-570. </li>
<li>Melendez LM, Yamka RM, Forrester SD, et al. Titration of dietary iodine for reducing serum thyroxine concentrations in newly diagnosed hyperthyroid cats [abstract]. J Vet Intern Med 2011 2011;25:683. </li>
<li>Melendez LM, Yamka RM, Forrester SD, et al. Titration of dietary iodine for maintaining serum thyroxine concentrations in hyperthyroid cats [abstract]. J Vet Intern Med 2011;25:683. </li>
<li>Yu S, Wedekind KJ, Burris PA, et al. Controlled level of dietary iodine normalizes serum total thyroxine in cats with naturally occurring hyperthyroidism [abstract]. J Vet Intern Med 2011;25:683-684. </li>
<li>Patrick L. <a href="http://www.ncbi.nlm.nih.gov/pubmed/18590348" target="_blank">Iodine: deficiency and therapeutic considerations</a>. Altern Med Rev 2008;13:116-127. </li>
<li>Fascetti AJ, Delaney SJ. Nutritional management of endocrine disease In: Fascetti AJ, Delaney SJ, eds. Applied Veterinary Clinical Nutrition. Chickester, West Sussex: Wiley-Blackwell, 2012;289-300.</li>
</ol>
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Dr. Mark E. Petersonhttp://www.blogger.com/profile/10804290441832222507noreply@blogger.com5