Addison's disease in dogs causes potentially fatal cortisol and aldosterone deficiency that is often missed for months because its episodic signs mimic many other conditions, requiring a high index of suspicion.
Addison's disease imposes a unique welfare burden through delayed diagnosis. Dogs in the pre-diagnosis period experience repeated episodes of profound weakness and nausea that are explained and treated ineffectively for weeks to months. The Addisonian crisis - complete adrenal failure - is a terrifying medical emergency for both dog and owner. After diagnosis, the welfare outlook is excellent: replacement therapy enables completely normal life. The welfare priority is reducing diagnostic delay through increased awareness of Addison's in episodic illness presentations in predisposed breeds.