Feline Hyperthyroidism

Hyperthyroid disease or hyperthyroidism in cats is the most common glandular (endocrine) condition in cats with an average onset of 13 years of age (95% of cases are in cats older than 10 years). Hyperthyroidism is most often caused by the increased production of the thyroid hormone thyroxine (T4) which leads to increased metabolism and general systematic stress on the feline's organ systems. The wonderful Issaquah veterinarians at Meadows Cat Hospital are highly trained in feline veterinary care and are well-versed in recognizing the signs and symptoms of hyperthyroidism early & thus recommending expedient blood work that can often save lives.

The staff at our family-owned cat clinic in Issaquah is adept at recognizing the early signs and symptoms of Feline Hyperthyroidism. These signs include unexplained weight loss (in >95% of cats) with increased appetite, increased vocalization, matted and oily or poor condition hair coat, increased metabolism and activity or restlessness along with weight loss, vomiting and diarrhea, racing heartbeat, panting or difficulty breathing and otherwise not doing well. Since recognizing many of these signs and symptoms does not require you to be a cat veterinarian, keeping a watchful eye on the health and condition of your feline is always vital. Once you are at our veterinary hospital in Issaquah WA, we can run the appropriate blood work and diagnostic tests to check for hyperthyroidism. If a cat is hyperthyroid or at risk of becoming hyperthyroid, the best defense is twice yearly exams and blood work.

If your beloved fur-baby has been diagnosed with feline hyperthyroidism, the good news is we have several treatments we can offer including medications and potentially curative radioactive iodine treatment (offered offsite). The medication of choice for treating feline hyperthyroidism is methimazole or felimazole, which can be administered orally or transdermally (a gel that absorbs through the ears/skin). Once we start treatment with methimazole, after 2-3 weeks we will give your cat a recheck exam in our cat hospital to look for the signs and symptoms of residual hyperthyroid damage and check the thyroid hormone levels to ensure the right dosage of methimazole. If all is well, we recommend 6-month rechecks with bloodwork. This bloodwork is important not only to check thyroid levels but to also check liver and kidney function which may be affected by the medication in 10-15% of cats.

Regardless of the choice of treatment, your trusted Issaquah veterinarian must take the time to educate you about the treatment options and the budget involved while you are visiting your veterinary clinic. Long-term, between bloodwork, recheck exams, and medication costs, treatment costs can quickly eclipse more pricey (but often single-expense) radioactive iodine. Having said that, radioactive iodine is not appropriate for every cat so you and your cat vet must discuss the potential kidney disease or heart damage that may be unmasked when your cat is "cured" of hyperthyroidism. Due to the cost and complications (including but not limited to parathyroid damage, nerve damage, etc.), thyroidectomy (surgical removal of the thyroid) is not recommended and rarely practiced.