Treatment for Hyperthyroidism in Cats at Sunnyvale, CA

Hyperthyroidism, the overproduction of thyroid hormones, is a common disorder in middle-aged to older cats. It results from overactive thyroid tissue. Some cats can have active thyroid tissue outside the thyroid gland, in other areas of the neck and/or chest. Thyroid hormones have many actions in the body, including affecting metabolism as well as heart function.

Clinical signs of hyperthyroidism in cats can vary. The most commonly reported signs include weight loss despite a good appetite, increased energy, and/or increased thirst and urination. A smaller group of cats may present with decreased appetite, decreased energy, or other signs. As thyroid hormones can affect the heart, heart murmurs or abnormal heart rhythms can be noted.

Diagnosis of hyperthyroidism requires a physical exam and blood work. If any abnormal heart sounds or rhythms are noted, chest radiographs (“x-rays”) may be recommended.

In general, feline hyperthyroidism carries a good prognosis with treatment. Treatment is aimed at destroying or removing the overactive thyroid tissue. Daily medication is not curative but can often provide long-term control. Medical management is usually the first treatment initiated, as it allows the doctor to monitor response to therapy. It also allows the doctor to monitor for signs of any other conditions, as the thyroid levels normalize, that may have been masked by the overactive thyroid status. There are two potentially curative treatment options available, radioactive iodine or surgical removal of the thyroid tissue. Radioactive iodine is given in special facilities; due to the nature of the treatment, the patients have to stay isolated for several days after treatment. Most patients only require one treatment. Radioactive iodine addresses overactive tissue in any location in the body. It is an especially good option for younger or otherwise healthy cats. Surgical removal of the affected thyroid tissue is uncommonly done and not usually recommended. It does not address possible active thyroid tissue outside the thyroid gland and can be associated with significant post-surgical complications.

Once receiving treatment, cats are monitored via clinical signs, physical exams, and blood work.

If your cat is suffering from Hyperthyroidism, please bring them to our Sunnyvale veterinarian today. Arroyo Animal Clinic is a full-service clinic that prides itself on providing compassionate health care for your Pets. Contact us today for more information on our services.


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