Information for Veterinarians Referring
Hyperthyroid Cats for Radioiodine Therapy

Thank you for considering referring your patient to our facility. Our goal is to provide the highest quality service in a timely fashion. The following is a list of instructions that can help us to achieve that goal.

1.) We appreciate the opportunity to communicate with referring veterinarians both during and following the patient's hospitalization for radioiodine therapy. Please provide us with current contact information to ensure we can update you promptly regarding the status of your referred patient. (Generally contact information is included on most veterinary diagnostic laboratory results print outs.) If you have recently moved or had a change of area code, please send along a current business card to allow us to update our records.

2.) In an effort to provide our patient's with the most comprehensive care possible, a thorough laboratory analysis, including a complete blood count, chemistry panel, electrolytes, thyroid hormone (T4), viral screening (FELV and FIV), urinalysis and thoracic radiographs are required within the past 45 days prior to treatment. Most or all of these tests are usually performed by the referring veterinarian. Cats on chronic (> 3 months) methimazole therapy will require a current T4 measurement off of methimazole for at least 7 days. This can be performed by the referring veterinarian or at our facility upon admission for radioiodine therapy. Cats with severe thyroid hormone elevations (T4 > 20 µg/dl) or cats on chronic (> 1 year) methimazole therapy for hyperthyroidism may suffer significant cardiovascular decompensation upon withdrawal of methimazole. To avoid the potential for possibly life threatening cardiovascular decompensation, cats managed with methimazole in excess of 1 year, or cats with total T4 levels in excess of 20 µg/dl should discontinue methimazole administration only 1 day prior to their appointment for radioiodine therapy.

3.) Cats suffering from upper respiratory viruses are often highly contagious to other cats. PLEASE notify us ASAP before hospitalization, if your patient is demonstrating symptoms of an upper respiratory virus (e.g. sneezing, congestion, nasal or ocular discharges) or if your patient has a history of chronic respiratory virus infection. Appropriate isolation of these cat’s is the only way to avoid unnecessary spread of the virus to other feline patients in our care. We have a seperate radioiodine isolation ward that can be utilized for this purpose.

4.) The cats treated with radioiodine usually remain hospitalized for a total of between 3 and 7 days following radioiodine therapy. The duration of the cat’s hospitalization will be determined by its rate of radioiodine excretion. The date of discharge from the hospital can only be estimated at admission.

5.) Because both California state and Federal regulations prevent visitation of cats treated with radioiodine during the mandatory hospitalization period, AVMI has installed individual iCat web cams for each of the Snyder Cat Cottages utilized by the hyperthyroid cats treated with radioiodine in our facility. These personal iCat web cams allow interested clients and referring veterinarians to continually observe individual cats hospitalized for radioiodine therapy at our facility.

6.) When picking up cats following hospitalization for the radioiodine treatment, a cat carrier is required. Furthermore, an absorbent towel placed in the bottom of the carrier is required. Infrequently cats will urinate during the car trip home and these precautions help minimize any cleanup efforts.

7.) Clients will be required to follow specific radiation safety precautions once their cat is returned to them. In brief these instructions include the use of a flushable/clumpable cat litter and the limited interaction between client and their cat for a precautionary period of approximately 14 days following discharge.

Download Information Handouts Below

These links allow you to download forms as PDF documents you can view and print from your computer.