Do Cats Throw Up From Hyperthyroidism?

Your vet can help take care of your sick kitty.
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It’s always scary when your kitty gets sick, especially if she’s ill enough to be vomiting. Hyperthyroidism can cause a range of symptoms, including a rapid heartbeat and excessive thirst as well as retching. If your pet shows any of these signs of trouble, take her to the vet right away.


The thyroid gland produces hormones that regulate metabolism. It works in conjunction with other glands, especially the pituitary. If the thyroid gland starts cranking out hormones, specifically thyroxine, at too high a level, hyperthyroidism results. Since the thyroid gland controls many different systems in the body, the condition affects each cat differently, which can make it hard to diagnose, even though hyperthyroidism is the most common disorder of the glands in cats.


The most common symptom of hyperthyroidism is increased appetite combined with weight loss. Other symptoms include frequent urination along with extreme thirst, so much so that the water seems to be running right through your cat. Often diarrhea is also a part of the mix, and she may seem hyperactive, pant a lot, start shedding abnormally and look rough and unkempt. About half the time, cats will vomit when they are suffering from hyperthyroidism. Other conditions, such as diabetes, can cause similar symptoms, and your pet needs to see the vet regardless of the cause.


A significant amount of weight loss and a rough appearance can make it seem likely that your pet is affected by hyperthyroidism, but blood tests provide a better answer. Since this condition is most common in older kitties, your vet will probably run some tests to check for diabetes and kidney failure. A blood test will show if your pet’s thyroxine (T4) levels are too high, but not all cats have evidence of hyperthyroidism show up in their blood work. X-rays may help, but in some cases, your vet may end up diagnosing the condition by ruling out everything else.


Your vet will recommend a course of treatment for your cat, based on his diagnosis of the cause and severity of the condition. One common treatment is antithyroid medication, used to slow the thyroid’s function. Another possibility is surgery to remove a tumor affecting the thyroid gland, which can completely cure the kitty. Or your cat could receive radioactive iodine therapy, which targets and destroys only the defective part of the thyroid gland.

Always check with your veterinarian before changing your pet’s diet, medication, or physical activity routines. This information is not a substitute for a vet’s opinion.

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