Hyperthyroidism in cats

A very common problem in older cats is hyperthyroidism, where the thyroid gland is overactive. Symptoms are hunger, loose motions, weight loss and a gaunt appearance. It is a relatively new diagnosis and has only be commonly found since the late 1980s. There have been many studies as to why this should have suddenly started to occur. The most likely reason is the change from steel to aluminium in canned foods. The problem seems only to occur in cats fed on tinned food. Diagnosis is simple and done by a blood test. A full blood profile should be run as many of these cats have problems with kidney or cardiac function due to the thyroid problem.

Three treatment options are available for hyperthyroidism. First we can give tablets three times daily, second we can surgically remove the gland and finally, referral for radiotherapy using radioactive isotope of Iodine. Of these, radiotherapy is best. The cat would be kept hospitalised for three to four weeks while radiation levels reduce. The levels of radiation given are not dangerous and give a complete cure. For prevention, we advise feeding good quality dried food. You must make sure the diet is suitable as the sole feed. Poor quality dry food may lead to problems with the urinary tract. Ask your practice if they would recommend the diet you are feeding.