Radioactive Iodine Treatment

Carp Road Animal Hospital

1054 Carp Road
Stittsville, ON K2S 1B9



fluffy cat

What is Hyperthyroidism?   

The thyroid gland regulates the body's metabolic rate.  Your hyperthyroid cat has a tumor (98% are benign) that is producing too much thyroid hormone.  This keeps the cat's "engine" running at an abnormally high speed.  This hyperthyroid state is very damaging to many areas of the body, including the heart, kidneys and eyes.

About This Procedure

Iodine 131 (I-131) is a radioactive substance that requires only one administration which can be oral or by a subcutaneous injection.

The I-131 is absorbed into the thyroid and will destroy only the thyroid tumor in 96%-97% of cats after just one administration.

By law, this therapy requires a clinical stay of approximately four to ten days.  Your cat's thyroid function should become normal within one to two months and should not require any thyroid supplementation.

Why I-131 is the Treatment of Choice

  • Cost Effective
  • Eliminates daily pilling
  • Painless Administration
  • Does not require anesthesia
  • Does not affect healthy thyroid tissue
  • Does not damage any other tissue or organs, including parathyroid glands
  • Destroys thyroid tumor, regardless of location

For more information on the background of Hyperthyroidism in cats there is a very good article from the New York Times Magazine.  You can read it here.

To obtain treatment for your cat please contact your regular veterinarian.