Felix had hyperthyroidism!

Felix was a lovely old tabby cat. He had always been keen on his tucker. In fact, if the honest truth be admitted, Felix had always been fat! His owner noted that as he got older, he kept on eating well but seemed to lose a bit of weight. Oh well, she thought, he’s just getting older. Then over the next few months Felix became positively ravenous but still kept losing weight. He also had a little diarrhoea from time to time and seemed to vomit every now and then. He drank a lot. But overall he seemed quite bright. In fact, for an old man he seemed to have a lot of energy!

Felix came in for his routine vaccinations and a scheduled senior blood test. This turned up some unexpected findings – Felix was hyperthyroid!

What did this mean for Felix? Would he be ok? Could he be treated and what was his prognosis?

Hyperthyroidism is a condition in which a small tumour grows in the thyroid gland in the neck. The good news is that this tumour is almost always benign. The disease arises because this little tumour pumps out excessive thyroid hormone. Our thyroid is a powerful little gland. It sets our metabolic rate. So poor Felix was stuck in fifth gear when he really should have slowed down to third! His metabolism was charging along at an excessive rate. This explains why he was eating so much but just unable to keep his weight up. It also explains his boundless energy for an old boy, his increased thirst and the diarrhoea and vomiting. Less obvious changes included elevated blood pressure and an excessively high heart rate that can really stress that heart muscle! Hyperthyroidism is a disease that needs to be treated but there are several really good options these days. Good news for Felix.

Medications – Felix could have had twice daily tablets or a preparation of medication applied to his inner ear flap. These medications lower the thyroid back into the normal range. They are life long and blood testing is needed to check that all is well controlled.

Diet – Another option would be a strict diet of Hills prescription diet y/d. This is a new method of treatment based around a very well designed diet that limits iodine, an essential building block for the thyroid hormone. So long as Felix stuck to this food only his hyperthyroidism could be controlled.

Radioactive iodine – However, Felix’s owner decided to go for radioactive iodine. This treatment offers a cure for hyperthyroidism. The thyroid gland takes up the radioactive iodine, administered as a pill. The dose is carefully calculated to destroy just enough of the tumour that Felix ended up with a normal thyroid level! Fabulous.

After treatment Felix gained a healthy amount of weight. He slowed down a lot and started taking more ‘senior moment’s’ in the sun. His coat became glossy and he stopped having diarrhoea. A great result for Felix!

If you are worried your cat might have hyperthyroidism then schedule a health check today. Blood testing will diagnose the disease and as you can see from Felix’s story, there a lots of great treatment options out there.