Introduction

The goals of treating feline hyperthyroidism are to return serum thyroid hormone levels to normal if possible and to eliminate the clinical signs of disease. This more specifically means increasing the cat’s weight and overall body condition and maximizing its quality of life. Depending upon the exact cause of the disease, treatments may consist of medication, surgery and/or or radioactive iodine therapies. Since hyperthyroidism is not an acute disease, emergency therapies are rarely necessary.

Treating Hyperthyroidism in Cats

Medical Therapy

By far the most common treatment for feline hyperthyroidism is lifelong daily administration of oral medication that reduces the function of the thyroid gland and thus reduces secretion of thyroid hormones. Frequently, once cats start on this course of therapy, underlying renal problems can surface. Your veterinarian will watch for this during the early course of medical treatment.

Surgical Therapy

If the hyperthyroid condition is the result of a tumor on one or both lobes of the thyroid gland, surgical removal of the gland (called a thyroidectomy) is possible and can possibly be curative. If only one lobe is affected, the cat may not require further treatment or medication, although it is possible that the remaining lobe will eventually become hyperactive. If both lobes need to be and are removed, the cat will require oral thyroid hormone replacement therapy for the rest of its life.

Radioactive Iodine Therapy

Radioactive iodine therapy is considered to be a safe and highly effective form of treatment for feline hyperthyroidism. In fact, it is considered to be the best therapeutic option for long-term control of this disease in cats, as long as the kidneys are not damaged. This treatment destroys all thyroid tissue. The availability of veterinary facilities that offer this treatment is somewhat limited, but is increasing. The protocol requires special handling facilities and post-therapy isolation for several days to weeks due to radioactivity.