VCA Animal Care Center of Sonoma County

Radioactive iodine therapy for feline hyperthyroidism

Radioiodine (I-131) Therapy & Feline Hyperthyroidism
Just like humans, cats have a gland called the thyroid that regulates metabolic rate. The condition 'hyperthyroidism' occurs when this gland overproduces thyroid hormone. One of the most effective treatments for this disease is Radioiodine (I-131) therapy.

  • I-131 treatment can completely cure hyperthyroidism.
  • Most cases (95%) never need another treatment of any type for hyperthyroidism. Only a very small number of cats require additional I-131 treatment or supplemental thyroid medication.
  • A single injection of radioiodine is absorbed into the hyperactive thyroid tissue, leaving the normally functioning thyroid tissue intact.
  • I-131 treatment does not produce harmful side-effects, require any pills, anesthesia, or surgery which greatly reduces the risks associated with more invasive or long-term therapies.
  • Normal thyroid function usually returns within four weeks after a Radioiodine treatment.

A consultation with Dr. De Haan will start the process to determine if your kitty is an appropriate candidate for Radioiodine therapy. Once confirmed, the I-131 therapy can be scheduled.

After a simple single injection of radioiodine, your pet will need to stay in our special radiation isolation facility for about 5 days. After three weeks of a slightly modified home routine, your pet can return to all of their normal activities and enjoy the benefits of a healthy, long and full active life with you and your family.


General Practice

We have over 600 animal hospitals in 41 states and 4 Canadian provinces that are staffed by more than 3,000 fully-qualified, dedicated and compassionate veterinarians, with more than 400 being board-certified specialists.

The nationwide VCA family of general practice hospitals give your pet the very best in medical care, providing a full range of general medical and surgical services as well as specialized treatments such as wellness, spay/neuter, advanced diagnostic services (MRI/CT Scan), internal medicine, oncology, ophthalmology, dermatology, cardiology, neurology, boarding, and grooming. Services may vary by location.

Our family of pet hospitals stands out by delivering the greatest resources in order provide the highest quality care available for your pets. By maintaining the highest standards of pet health care available anywhere, we emphasize prevention as well as healing. We provide continuing education programs to our doctors and staff and promote the open exchange of professional knowledge and expertise. And finally, we have established a consistent program of procedures and techniques, proven to be the most effective in keeping pets healthy.

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Emergency Care

VCA Animal Care Center provides round-the-clock emergency services to care for your pet when your family veterinarian is not available. We have six veterinarians and many technicians on staff that specialize in emergency services and critical care to attend to any type of small animal emergency including trauma, toxin exposure, surgical and medical crises, just to name a few. Our experienced staff continually receives advanced training specific to emergency practices and procedures to insure your pet gets the best care possible.

In addition to emergency services, we are able to provide intensive care for critically ill pets that have been referred by family veterinarians. Our clinicians are on staff 24 hours a day, every day of the year, including weekends and holidays, allowing us to monitor and provide continuous care.