Hyperthyroidism In Cats

Hyperthyroidism: Unfortunately, this one of the most common problems seen in geriatric and older cats. The average age of onset is 13. It’s an insidious disease that results in many other related afflictions due to the increased level of thyroid hormone, T4, released from the paired glands located in the laryngeal area of the neck. This T4 is then changed into the active thyroid hormone, T3, by tissues in the body. Hyperthyroidism, if not treated, can result in irrecoverable damage to the kidneys, liver and heart. However, if diagnosed early and treated with radioactive iodine, the associated diseases can be minimized. Recognizable symptoms include weight loss with increased appetite, polydipsia or increased water consumption, unusual vocalization, hyperactivity and sometimes chronic vomiting and diarrhea. Hyperthyroid cats can be demanding, even obnoxious in their desire for food and treats. Diagnosis involves testing of the blood for increased T4 hormone (two specific tests) and/or a T3 suppression test. Treatment, as mentioned earlier, involves radioactive iodine administered in a special clinical setting. There is also a medication (methimazole), while not a specific treatment, can interfere with the conversion of the T4 to the active T3. See the following article for more detailed information: