What is hyperthyroidism?
Your cat has two thyroid glands in their neck that control their metabolism.
Hyperthyroidism is over-activity in these thyroid glands. The vast majority of cases are caused by harmless swellings but some rare cases are caused by cancer (1-3% of cases).
Hyperthyroidism causes a high metabolism, which has many negative effects on the body. Weight loss, a high heart rate and high blood pressure are just a few of the common problems encountered by hyperthyroid cats.
Symptoms appear slowly, so you may not notice a problem at first but left untreated over a long period, hyperthyroidism can be fatal.
Hyperthyroidism is most common in middle aged to older cats.