Feline hyperthyroidism is the most common endocrine disorder in middle aged and geriatric cats. Symptoms can include behavioral changes, hyperactivity, weight loss, increased appetite, increased thirst and urination, vomiting, diarrhea, and rapid heart rate. Often affected cats may have an unkempt coat that appears matted and/or greasy. Most cats respond quite well to treatment and have a good prognosis. Cats with severe disease or those that have developed further complications may have a more guarded prognosis.

Your veterinarian may diagnose hyperthyroidism through physical examination as well as through routine laboratory findings indicating elevated thyroid hormone levels in the blood.  Once a diagnosis of hyperthyroidism is made, your veterinarian will discuss options for treatment, which may include anti-thyroid medications, diet, surgery, or radioactive iodine (I-131).

How to know if Radioactive Iodine (I-131) Treatment is right for your Cat

Your veterinarian can help you decide if radioactive iodine (I-131) is a good option for your cat.  If so, a few pre-screening tests will need to be performed prior to administering the treatment. These tests allow for further evaluation of the severity of the disease and to determine if any other organ systems are involved. The screening tests include:

• A blood chemistry profile to screen for underlying illnesses such as kidney disease. This routine blood test can be performed by your veterinarian.
• A urinalysis is an additional screening test for kidney disease that can be performed by your veterinarian.
• A thyroid scan (nuclear scintigraphy) is performed at Animal Imaging to evaluate the thyroid itself and give us a better understanding of the disease. The thyroid scan will allow us to evaluate how much of the thyroid gland is affected and help us determine if the disease is benign or malignant.
• Chest and abdominal radiographs (x-rays) are also performed at Animal Imaging as part of the thyroid work up to screen your cat for any overt problems with the heart, lungs, or abdominal organs that may warrant additional diagnostics prior to treatment.

Once these tests are completed, our board-certified radiologists can determine if your cat is a good candidate for the treatment of hyperthyroidism with radioactive iodine. If so, Animal Imaging can provide a safe and effective treatment in a comfortable environment.