Hyperthyroidism is a very common disease seen in cats when a portion of their thyroid gland(s) becomes overactive. Just like dogs, cats have two thyroid glands located on either side of the windpipe and regulate the body’s metabolism.
Hyperthyroidism is diagnosed with a blood test that checks the thyroxine (T4) levels in the body. Once diagnosed, your veterinarian will set up the proper treatment plan that works best for you and your cat.
Medication tends to be the most common option. Medication blocks the production of the thyroid hormone. Once on the prescription for 2 weeks another blood test is needed to check the levels, this ensures the proper dosage your pet needs to stabilize the hormone in the body. At this time it is recommended to also check the kidney values to make sure they are functioning properly. Medication is life long and annual blood tests are needed to make sure that the thyroid levels are being maintained.
Food is another option. It comes in both a wet and dry formula and has been proven to restore thyroid health in 3 weeks. No other food or treats can be given; this ensures that the food is working to its full effect.
Another option that not many people may know about is radioiodine treatment. Thyroid glands absorb iodine, even more so in hyperthyroid cats. With radioiodine treatment a radioactive form of iodine is given, the radiation destroys the portion of the gland that is not functioning normally. After treatment cats experience normal thyroid function. Your cat will have to be hospitalized at the clinic in which the treatment is being done. The time depends on how well your cat’s body absorbs the iodine, and visiting them is not an option. This treatment is only recommended in healthy, stable hyperthyroid patients.
Senior cats are generally affected, over the age of 10. Symptoms include weight loss, muscle loss and increased appetite; this is due to the metabolism being faster than it should be. The body is using up calories just as fast as your cat consumes them. Your cat may seem restless, hyper, cranky or even aggressive. They may appear like a stray cat having a thin, poor hair coat and looking a little bit scraggly. An increased heart rate, higher temperature, panting or difficulty breathing can also be noted. In some cases your veterinarian can palpate the thyroid glands as they become much bigger than normal.
In later stages of hyperthyroidism you may notice that your cat becomes weak and lethargic. They may become hypertensive (high blood pressure), and/or develop heart problems. If left untreated hyperthyroidism affects all of the organs in the body and can be fatal.
Here at McLean Animal Hospital we are very familiar with hyperthyroidism, treatment and long term care. If you have any questions, concerns or would like to book an appointment please do not hesitate to contact us at 416-752-5114.
Thank you for reading!
by Sarah Higney, Veterinary Technician