Hyperthyroidism is the most common hormonal disorder in older cats and causes significant suffering if undetected or poorly managed.
Untreated hyperthyroidism causes cats to experience persistent hunger despite eating well, as the high metabolism burns calories faster than they can be consumed. Affected cats often feel anxious, over-stimulated, and may develop dangerous heart conditions. Early detection through routine senior bloodwork and prompt, consistent treatment dramatically improve welfare outcomes. Owners of older cats should schedule annual thyroid screening.