Hyperthyroidism is the most common hormonal disorder in cats over ten years old, causing significant suffering if undetected but highly manageable with early diagnosis and appropriate treatment.
Hyperthyroid cats experience persistent metabolic discomfort — chronic hunger that cannot be satisfied, restlessness, gastrointestinal upset, and in advanced cases, the distress of heart failure and kidney disease. Cats are adept at concealing illness, making owner vigilance and regular senior wellness checks critical. Weight loss in a cat eating well should always prompt veterinary investigation. Once diagnosed, most cats respond well to treatment, with rapid restoration of body condition and behaviour. Untreated hyperthyroidism is a prolonged source of suffering that is entirely preventable with annual screening blood tests in senior cats.