What is Feline Hypothyroidism?

Hypothyroidism is an endocrine gland disorder. (The thyroid gland is considered the "master gland" of the endocrine glands.)

Hypothyroidism is relatively rare in cats, and it is not considered fatal, although it can affect a cat's quality of life.

What causes hypothyroidism in cats?

Although there are studies which indicate hypothyroidism might be an inherited disorder in dogs, most cats develop hypothyroidism in one of two ways:

• Injury to the gland through surgery
• As a result of radioactive iodine therapy for hyperthyroidism. Although conventional thinking was originally that only two to five percent of cats were affected this way, it is now believed that the odds may be much higher, as much as 30% or more.

Hypothyroidism may also be associated with thyroid tumors if a cat's diet is low in iodine. This is relatively rare today, as most commercial pet foods contain a sufficient quantity of iodine.

What are the symptoms of hypothyroidism in cats?

Hypothyroidism may present with one or more of these symptoms:

• Weight Gain
  The cat will have an increased appetite and may also drink more water.
• Dull, Dry Coat
  This may also be accompanied by hair loss and excessive grooming.
• Listlessness and Lethargy
  The cat may lose interest in playing or socializing with other cats.

How is feline hypothyroidism diagnosed?

Hypothyroidism is diagnosed through a blood panel and testing of thyroxine levels through T-3 and T-4 tests.

How is feline hypothyroidism treated?

Fortunately, this condition is easy to treat. Thyroxine supplement is given, usually through pills, although gels or flavored formularies may also be available.

Cats with controlled hypothyroidism may continue to live long, happy lives.