Companion Animals

Cat Hyperthyroidism and Senior Health

Hyperthyroidism is the most common hormonal disorder in older cats, causing progressive deterioration including weight loss, hypertension, and cardiac disease if untreated.

Key Facts

Hyperthyroidism affects approximately 10% of cats over 10 years
It is caused by a benign tumour of the thyroid gland in most cases
Signs include weight loss despite good appetite, vocalisation, and restlessness
Treatment options include medication, radioiodine, surgery, or dietary management
Untreated hyperthyroidism causes hypertension, blindness, and cardiac failure

Welfare Considerations

Hyperthyroidism causes significant chronic suffering including hunger, anxiety from elevated metabolism, and ultimately cardiac and hypertensive complications. Early detection through annual blood screening in cats over eight years dramatically improves welfare by allowing treatment before complications develop. Radioiodine therapy is curative with minimal welfare cost to the cat during treatment.

What You Can Do

Request annual blood and urine testing for cats over eight years
Learn the signs of hyperthyroidism in older cats
Discuss treatment options with your vet if hyperthyroidism is diagnosed
Consider radioiodine as a curative option where available
Monitor treated cats for return of clinical signs or development of kidney disease