Search

Feline Hyperthyroidism and Radioactive Iodine Treatment

Updated: Oct 8, 2021

Did someone say radioactive cat? 🤣


When Milo presented to Goodna Vet Surgery at the start of 2020, his owners knew something just wasn’t right. Milo had suddenly become ravenous – eating all his food but still asking for more! He had also started vomiting and eating grass. After a thorough check over by Dr Lauren, a comprehensive blood test was performed, proving that his thyroid level was too high.


Milo was diagnosed with hyperthyroidism. Hyperthyroidism is the most common endocrine disorder found in cats, affecting up to 11% of older cats worldwide. It is characterised by an increase in the production and secretion of thyroid hormone responsible for regulating the body’s metabolic rate. Signs often attributed to hyperthyroidism include an increased appetite, weight loss, agitation, increased drinking and urinating, vomiting and diarrhoea, panting, and poor coat quality. Unfortunately, several common diseases can look very similar, including diabetes mellitus, chronic kidney disease, or certain types of cancer - and further diagnostics are required to determine the underlying cause.


Milo was started on medical therapy for hyperthyroidism, and his owners diligently applied the medicated ointment onto his ears twice a day. As with any of our feline friends undergoing hyperthyroidism treatment, we closely monitored his progress with regular blood tests. It is important to check how the thyroid levels respond to the medication to help guide dose rates. These blood tests also help monitor for any changes to kidney values as hyperthyroidism can affect kidney health. Although it was difficult to achieve perfect control of Milo’s thyroid level with medication, he was very fortunate that his kidney levels remained healthy.


There are a few ways hyperthyroidism can be treated – medical therapy such as tablets and transdermal creams are a common first-line treatment choice. Another very effective treatment choice is radioactive iodine. Unlike lifelong medical therapy, radioactive iodine offers a cure for the disease, with an over 95% success rate. It is very safe and targets the abnormal overactive thyroid tissue.


After many months of dedication with medical management, we determined that Milo was a purrfect candidate for radioactive iodine treatment. Before Christmas 2020, Milo visited our friends at Brisbane Veterinary Specialist Centre for radioactive iodine treatment and a short stay in special isolation. He was discharged back home to his loving family on Christmas eve with some special handling instructions for a couple of weeks. His most recent recheck blood test, one month after treatment, found his thyroid level was back to completely normal and now doesn’t need any more medication! Needless to say, he was as happy as ever, and we can assure you, he doesn’t glow in the dark.


If your furry friend shows any of these signs, or if you wanted a blood test for a general health screen, please contact us and have a chat.


Dr Lauren Stack



116 views0 comments

Recent Posts

See All