Hyperadrenocorticism (Cushing's disease) is a common endocrine disorder in older dogs. Proper diagnosis and treatment can significantly improve quality of life.
Dogs with untreated Cushing's disease experience chronic discomfort from muscle wasting, skin fragility, distended abdomen, and persistent thirst and urination disrupting normal rest patterns. The psychological impact of cortisol excess — restlessness, panting, and behavioural changes — contributes to welfare deterioration. Medical management with trilostane (the preferred treatment in most countries) or mitotane significantly reduces cortisol levels and improves quality of life in most dogs. Signs of improvement include reduced drinking and urination, improved coat quality, and return of muscle tone. Treatment requires careful monitoring as too-aggressive cortisol suppression causes an Addisonian crisis. The welfare trade-off of treatment benefits versus monitoring burden is generally favourable for dogs with significant clinical signs.