Did you know that older cats can suffer from hyperthyroidism? This is a common condition in older cats and it is caused by overproduction of thyroid hormone. Symptoms include weight loss with an increased appetite, increased activity, vomiting, diarrhea, increased water consumption and increased urination. Thankfully, the condition can be treated with Radioiodine I-131 treatments and the success rate is over 95% with just one injection. I-131 is painless, very well tolerated and side effects are uncommon. Dr. Erick Mears has been treating hyperthyroid cats since 1993 and is one of the only internal medicine specialists that travels the country for this specialized therapy.