How to Detect Hyperthyroidism in Cats

Hyperthyroidism is a common endocrine disease in cats over seven years of age. An increase in the production of thyroid hormones by the thyroid gland causes hyperthyroidism. To detect hyperthyroidism in your cat, follow these steps.

Difficulty: Moderately Challenging

Instructions

1. Look for any behavioral changes that your cat exhibits. This may include frequent vomiting, diarrhea and an increase in urination. You may also see your cat eating more food or drinking more water than normal. Some cats even stop grooming themselves properly.

2. Weigh your cat. Approximately 90 percent of cats with hyperthyroidism show a significant weight loss. Contact the veterinarian right away, if your cat has lost a lot of weight.

3. Allow the veterinarian to look and listen for heart changes in your cat. Many cats with hyperthyroidism present rapid heart rates, sometimes over 200 beats per minute. High blood pressure and heart murmurs may also occur in hyperthyroid cats.

4. Feel for the cat's thyroid gland. Usually, the thyroid gland is small enough that a veterinarian can't feel it via an external examination. Cats with hyperthyroidism have a thyroid gland that is larger than normal, and a veterinarian usually can feel it upon examination. If this occurs, the vet will usually suspect hyperthyroidism, but will request further testing for a definite diagnosis.

5. Permit your cat's veterinarian to perform blood work on your cat. This blood work includes the measurement of thyroid hormone levels such as T4 (Thyroxine) and T3 (Triiodothyronine.) In hyperthyroid cats, T4 levels will be elevated. T3 levels may also be elevated in some hyperthyroid cats.

6. Rule out other possible diseases. Some of the symptoms of hyperthyroidism can have other causes, such as heart disease, kidney disease or diabetes. Lab tests such as urinalysis and a complete blood count (CBC) can help rule out these diseases.

Tips & Warnings

• The thyroid gland is located in the front of the neck, on either side of the cat's windpipe.
• Some hyperthyroid cats will show an increased amount of hair loss or shedding.
• The information in this article is not meant to serve as a substitute for regular medical advice and care. Be sure to talk to your cat's veterinarian if you suspect hyperthyroidism.