Hyperthyroidism is a relatively common condition in cats that are middle aged and older. The most common clinical sign of hyperthyroidism is weight loss, followed by an increased appetite. Other signs of hyperthyroidism may include increased thirst, urination, vocalization or agitation.

Hyperthyroidism results when the thyroid glands become overactive and secrete too much thyroid hormone. Thyroid hormone controls the body's metabolic rate and has an effect on almost every organ in the body. The cause(s) of hyperthyroidism are the subject of much research and are currently not well understood though it is thought that dietary factors may play a role.

Hyperthyroidism is very treatable, either by daily oral medication, feeding a special prescription diet, or by radioactive iodine treatment. Surgical removal of the thyroid gland(s) is also a treatment option, though not one usually advocated by All Cats Clinic.
Many cats with hyperthyroidism also have or will develop hypertension, or high blood pressure. Untreated, high blood pressure may lead to blindness, enlargement of the heart, or other complications. These changes can be reversible if the hyperthyroidism and hypertension are treated early enough.

Hyperthyroidism is usually diagnosed by a simple blood test. Occasionally two or more blood test are necessary to reach a diagnosis. If you have any concerns about your cat's thyroid health please call us to schedule an appointment today!

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All Cats Clinic


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