Feline hyperthyroidism is the most common endocrine disease in older cats, and effective management through medication, diet, or radioactive iodine dramatically improves quality of life.
Feline hyperthyroidism management is a welfare success story: a common, serious disease has multiple effective treatment options that restore normal quality of life. Untreated hyperthyroid cats experience chronic anxiety, muscle wasting, hypertension, and cardiac strain that owners frequently misattribute to normal aging. The racing metabolism creates a cat who appears active but is physiologically distressed. Diagnosis through a simple blood test and appropriate management through the owner's preferred approach returns affected cats to comfortable, healthy lives. Annual thyroid screening for cats over 10 is a welfare-positive preventive measure.