Feline Owner’s Guide to Hypothyroidism in Cats

Hypothyroidism in cats occurs when the thyroid gland produces too few hormones.  This condition is quite rare.  Although it isn’t life-threatening, it will significantly reduce your cat’s quality of life.  So, what exactly causes this condition to occur when it does?

Causes

Ironically, hypothyroidism in cats is usually caused by medical treatments for hyperthyroidism.  Hyperthyroidism occurs when the gland produces too many hormones.  It is treated with radioactive iodine or surgery to remove all thyroid tissue.  This in turn causes hypothyroidism.  Two other common causes include tumors affecting the gland and lack of iodine in the diet.

Symptoms

If your cat develops this condition, he will have an increased appetite and thirst.  He will also start to gain weight.  If you’re paying close attention, you will also notice that your cat starts grooming himself excessively.  His hair may be dry and itchy and eventually start to fall out.  Some cats also appear lethargic.

Diagnosis

If your cat comes in with symptoms of this condition, the veterinarian will perform a blood test.  This will allow him to determine the level of thyroid hormone circulating in the blood.  Some vets also elect to test your cat’s urine.

Treatment

As mentioned at the beginning of this article, hypothyroidism in cats is not a life-threatening condition.  However, it should still be treated as it will lower your cat’s quality of life. 

The disease is very easy to treat.  If it was caused by medications given to treat hyperthyroidism, your cat will have to stop taking them.  Other cases can be treated by prescribing supplemental hormones.  This medication will have to be taken orally once or twice a day.