Hyperthyroidism is the most common endocrine disease of older cats and causes significant welfare compromise if undiagnosed and untreated, yet responds very well to treatment.
Hyperthyroid cats experience chronic restlessness, weight loss, and cardiovascular strain. Many owners attribute signs to normal ageing. Annual screening blood tests for cats over 7 years old allows early diagnosis when treatment response is best. All three treatment options provide good welfare outcomes when appropriately chosen.