Radcats is a referral facility for the treatment of feline hyperthyroidism with iodine isotope 131.

The center was established in 1994 by Dr. Charles L. Ward at The Animal Hospital of Carrboro.  The treatment center is dedicated to the memory of B.J. Brown, a hyperthyroid cat whose owner assisted Dr. Ward with the original licensing procedure, program development, and treatment protocol. The center is currently directed by Drs. Erik Dorsch and DeWana Anderson, owners of The Animal Hospital since 2009.

Over 2,500 cats have been treated with I131 for feline hyperthyroidism at Radcats since 1994.

Iodine 131 therapy is a safe and effective method to quickly and permanently decrease abnormally high thyroid levels. Over 95% of all cats treated with a single dose of iodine 131 return to normal thyroid function over a period of 90 days.

The effects of unmanaged hyperthyroidism are stressful to both pets and their owners. We are pleased to offer this safe and effective treatment to restore health and quality of life to cats and peace of mind to their owners.


Feline Hyperthyroidism is one of the most common endocrine disorders in middle-aged and older cats. Reports estimate that one in three hundred cats are affected by hyperthyroidism. The thyroid glands are located in the neck and produce hormones that regulate cellular metabolism in all organs of the body.

The amount of thyroid hormone produced by the thyroid glands is regulated by the pituitary gland in the brain. The pituitary gland signals the thyroid glands to maintain proper levels of circulating thyroid hormone. This mechanism keeps cellular metabolism in balance. Most cases of feline hyperthyroidism are due to benign tumors called nodular hyperplastic goiters.

These tumors produce excess thyroid hormone and do not respond to regulation by the pituitary gland. Unfortunately, the thyroid tumor cannot always be palpated in the neck. Some cats will have thyroid tumor in the chest or other locations in the body. Any of these tumors can produce excessive amounts of thyroid hormone.

The signs and symptoms of hyperthyroidism are multi-systemic and relate to increased metabolic changes. Hyperactivity, weight loss, increased appetite, increased thirst, increased elimination, vomiting, diarrhea, panting, rapid heart rate, increased shedding, and occasionally lethargy have been observed. High blood pressure is a common clinical finding. Blindness due to retinal hemorrhage and heart disease (including heart failure) may also be associated with hyperthyroidism. Untreated hyperthyroidism is fatal.