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Cat Thyroid Center

Cat looking at its reflection


What happens when a cat is admitted to our Center?

Treatments are on Tuesdays.  Owners will be given a specific arrival time when the appointment is scheduled.  The cat may have breakfast on the day of treatment. Dr. Ott or Dr. Heaton examines the cat, reviews the pre-evaluation tests and x-rays, and discusses the medical history with the owner. When the cat is accepted for admission, the owner visits the treatment room.

Here is what happens in the treatment room: using an electric clipper, some fur is clipped from the patients flank area and then a small amount of saline solution containing radioactive iodine is injected. This takes less than a minute and the cat must lie still during this time.

After this painless injection under the skin, the cat goes to a cage or a spacious condo and the entertainment begins. During hospitalization, we provide favorite foods, diversions, and lots of “hands-on” care and affection. Each cat’s food, linens and litter are replaced several times a day. Owners bring an old T-shirt or some socks (unwashed) that have their familiar scent, and these items are used for bedding. Some owners bring a favorite toy. We have audiotapes of birds and a DVD to play special videos made for cats (Video Catnip is a favorite). Live entertainment is provided by “Radar” our pet bird and our aquarium. We offer a wide variety of food options, but do recommend you bring your cat’s favorites, especially those on a prescription diet.  We can cater to the most finicky of patients!

We specialize in personalized customer service and clinical excellence. Radioactive iodine therapy is our only specialty service. We give extra attention to each patient and maintain a standard of care that is equal to, or superior, to that offered by the finest medical centers for humans or animals. The patient’s family is called with progress reports during hospitalization. Our patients clear 90% of the radioisotope in 48 hours because they are content while they are here-eating, drinking and relaxing.  We have created a very warm, peaceful, and home-like environment for our patient’s comfort.

What is the recovery time?

You may see improvements in your cat’s behavior within a few days to weeks, but some cats require two or three months for all symptoms to disappear. As the cat’s metabolism returns to normal, body functions slow down. The formerly hyperactive cat becomes calmer. Along with a slower heartbeat and respiration, changes may include weight gain, better grooming, less vomiting, reduced appetite, fewer visits to the litter box, and more sleeping. Some cats gain one or more pounds in the first month. About 50% have normal thyroid blood tests after a month and most others reach euthyroid levels by 3 months.  A very small number of patients have taken up to 6 months for their thyroid levels to rebound.

What is post treatment care?

Using a Geiger counter, each patient’s radioactivity is monitored daily to ensure that the cat is clearing the isotope. Our radiation safety program requires a cat remain hospitalized until its radioactivity has dropped to very low levels that pose no threat to other pets or family members.

When the cat goes home after four days at the Center, it poses no danger to the family. We recommend that owners take a few common sense precautions for the next two weeks to limit their exposure to any residual radioactivity. Discharge instructions are reviewed with each owner and they receive a take home copy and additional reference materials.

The residual radioactivity is in the cat’s body secretions and excretions and a small amount is retained in the thyroid tissue. The cat does not need to be isolated, but pregnant women and children under the age of 18 years should not take care of the cat during the two weeks after treatment.

The small amount of isotope remaining, less than 10%, will pass in the urine and feces to the litter box. Until it passes, it generates low levels of gamma radiation. We recommend wearing disposable gloves when changing the litter and limiting your direct contact with your cat to 5 minutes a day. At a distance of three feet from the cat, there is minimal exposure to radiation. If you have questions regarding the treatment of Feline Hyperthyroidism and how we can help your cat, visit the contact page and fill out the Inquiry Form and a representative will contact you.

Does the radioactive injection hurt?

No, it is painless and given under the skin. There is no local skin irritation.

Must I isolate my kitty when she (or he) comes home?

You cannot hold your cat on your lap for more than a few minutes/day when she first comes home. But she can stay in the room with you as long as she is at least 3 feet away from you.

What is the oldest cat you have treated?

21 years old.

Why does Tapazole (methimazole) make my cat sick?

Tapazole (or Felimazole) has many side effects, including nausea, skin excoriations, autoimmune reactions, blood dyscrasias, vomiting and malaise. The side effects get worse when the dosage must be raised to control the disease.

My cat has diabetes, can it be treated?

Yes, we have treated many cats that are hyperthyroid and diabetic. We continue their prescribed diet and insulin during hospitalization.

Will vitamin supplements and other medications interfere with the treatment?

Some can interfere, particularly those containing sea kelp with lots of iodide. These must be discontinued prior to and during treatment.Most antibiotics do not interfere. Please discuss your cat’s medications and supplements with the staff prior to admission and bring the containers with you at the time of admission.

What are any possible adverse effects or complications from radioactive iodine?

Hypothyroidism can occur in 5% of patients. These cats are placed on a tiny, once a day thyroid supplement that can be added to their food and do well. Renal failure is unmasked in about 5% of the cases that we have treated. The kidneys are not perfused as well as they were in the cat with a racing heart and hypertension. The renal failure can be treated with diet or with fluids.

Where does my cat stay?

Your cat will be housed in a quiet, pleasant home-like environment in a completely separate part of the hospital. Live entertainment is provided by “Radar” our pet bird as well our fish.

May I visit my cat during the treatment?

No, once your cat has been treated, there can be no visitation except by authorized personnel. You may call us anytime for updates on your pet’s condition. If you have questions regarding the treatment of Feline Hyperthyroidism and how we can help your cat, visit the contacts page and fill out the Inquiry Form and a representative will contact you.