Hyperthyroidism (overactive thyroid gland) is a common condition of the older cat. It is caused by an increase in activity of the thyroid glands, usually due to a benign (non-cancerous) process. Cats have two thyroid glands and these are usually both affected, although one side may develop more of a problem first. The glands can become quite big, leading to a ‘goitre’ which can be felt by your vet.
Signs of hyperthyroidism include:
- increased appetite
- weight loss
- increased thirst
- hyperactive behaviour, restlessness
- unkempt hair coat
There are other conditions which can show similar signs. A blood test will be required to determine whether your cat has hyperthyroidism.
Many cats with hyperthyroidism will also have high blood pressure. This will need treating separately. Cats who have been treated for hyperthyroidism should also have their blood pressure regularly monitored as they are at higher risk of getting high blood pressure.