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Hyperthyroidism

Quick answer

Overactive thyroid glands in middle-aged and older cats, raising metabolism. Common signs include weight loss despite a good appetite. See your vet if an older cat loses weight while eating well, or shows persistent vomiting with behavioural changes.

Definition

Overactive thyroid glands in middle-aged and older cats, raising metabolism. Common signs include weight loss despite a good appetite.

Symptoms

  • Weight loss with increased appetite
  • Hyperactivity or restlessness
  • Increased thirst
  • Vomiting and diarrhoea
  • Poor coat and rapid heart rate

When to see a vet

See your vet if an older cat loses weight while eating well, or shows persistent vomiting with behavioural changes. Blood tests confirm the diagnosis.

Related guides & tools

Frequently Asked Questions

What is Hyperthyroidism?
Overactive thyroid glands in middle-aged and older cats, raising metabolism. Common signs include weight loss despite a good appetite.
What are the symptoms of hyperthyroidism?
Common signs include Weight loss with increased appetite, Hyperactivity or restlessness, Increased thirst, Vomiting and diarrhoea. This is not a complete list — individual pets vary. See linked guides for fuller context.
When should I see a vet about hyperthyroidism?
See your vet if an older cat loses weight while eating well, or shows persistent vomiting with behavioural changes. Blood tests confirm the diagnosis.