Jun 29, 2011 02:02PM
● By By: Suzi Harkola
Hyperthyroidism is one of the most common diseases of the middle-aged and older cat. Like diabetes, it is a multi-system disorder caused by an increase in the amount of thyroid hormones produced by an enlarged thyroid gland. It was first documented in cats almost 30 years ago, but the cause of the disease has been elusive. It is usually non-cancerous, but is caused by a hyperactive thyroid.
The most common signs of hyperthyroidism in cats include weight loss (for example, from 15 to 12 pounds), increased appetite, vomiting, increased thirst and urination, hyperactivity, and diarrhea. The coat may appear matted or greasy.
You know your cat better than anyone else. If you see any of these symptoms, see your veterinarian for diagnosis and treatment.
“If the thyroid hormones are elevated, we recommend intervention to calm the development of heart disease. As a cat ages, hyperthyroidism may develop an enlargement and thickening of the heart. If left untreated and unmanaged, these changes will eventually compromise the normal function of the heart, and can even result in heart failure. Once the cat is treated, the cardiac changes should improve and even resolve.”
“Once hyperthyroidism has been confirmed, there are essentially three treatment options,” Dr. Watkins explained. “Cats can be given an anti-thyroid pill, twice a day. This works well, but is a life-long requirement. A second option, which is initially more expensive, is radioactive-iodine therapy, administered as an injection and absorbed into the bloodstream. Prognosis is good, usually giving your cat another eight or nine years of quality life. The third option, surgery, is rare.”
The American Association of Feline Practitioners (catvets.com) notes that the advantages of radioactive-iodine therapy are that the procedure is curative in approximately 95% of all cases, and can be repeated. It has no serious side effects, and does not require anesthesia.
There’s no significant risk for the cat, but precautionary protective measures are required. The cat must remain hospitalized for a short period of time after treatment, and most facilities licensed for this procedure will not allow visitors. If other symptoms continue, thyroid-hormone supplementation may be required.
Monitor your cat’s behavior. If you see anything out of the ordinary, don’t wait to call your veterinarian, and always schedule an annual visit for immunizations and physical examination.
Dr. Watkins is a graduate of the University of Illinois and has been treating pets for more than 30 years. His office is located at 4141 South Tamiami Trail, Suite14 in Sarasota, 941-925-7387.