Hyperthyroidism

Hyperthyroidism

Species: Cat

Breeds Affected: All breeds (primarily senior cats)

An overproduction of thyroid hormone caused most often by a benign adenoma in the thyroid glands. It is the most common endocrine disorder in older cats and leads to increased metabolism, weight loss, and potential complications such as heart failure.

• Weight loss despite a ravenous appetite
• increased thirst and urination
• hyperactivity or restlessness
• vocalization
• unkempt or greasy coat
• intermittent vomiting and diarrhea
• and on physical exam
• a fast heart rate and possibly an enlarged thyroid gland.

Multiple treatment options exist. Lifelong oral methimazole is commonly used to block thyroid hormone synthesis. Curative treatments include radioactive iodine (I-131) therapy and, less commonly, surgical thyroidectomy. An iodine-restricted diet may also help manage the condition.

Methimazole (Tapazole®) administered orally or transdermally; radioactive iodine (I-131) therapy as a one-time treatment; beta-blockers (eg, atenolol) to control heart rate; iodine-restricted diet (eg, Hill's y/d); in some cases, amlodipine may be added if hypertension is present.

• Columbus Veterinary Reviews , Columbus
• The Veterinary Relief Company , Columbus
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• East Columbus Veterinary Hospital , Columbus