Hyperthyroidism is the most common hormonal disorder of middle-aged and elderly cats, causing a range of welfare-compromising symptoms that are effectively managed with appropriate treatment.
Hyperthyroid cats suffer from a persistent state of metabolic overactivity that causes chronic discomfort, weight loss despite constant hunger, restlessness, and cardiovascular stress. The disease is well-managed once diagnosed but frequently underdiagnosed because owners mistake weight loss and increased vocalisation in older cats for normal ageing. Regular thyroid screening in cats over 7 years enables earlier diagnosis and treatment before cardiovascular complications develop. The multiple treatment options mean that management can be tailored to individual cat and owner circumstances, but the welfare imperative is diagnosis and treatment rather than acceptance of decline.