Addison's disease (also known as chronic adrenal insufficiency, hypocortisolism or hypocorticism) is a rare endocrine disorder in which the adrenal gland doesn't produce enough steroid hormones (glucocorticoids and often mineralocorticoids). It may develop in children and adults, and may occur as the result of many underlying causes.

The condition is named after Dr Thomas Addison, the British physician who first described the condition in his 1855 publication On the Constitutional and Local Effects of Disease of the Suprarenal Capsules.[1] The adjective "Addisonian" is used for features of the condition, as well as patients with Addison's disease.[2]

The condition is generally diagnosed with blood tests, medical imaging and additional investigations.[2] Treatment involves replacement of the hormones (oral hydrocortisone and fludrocortisone). If the disease is caused by an underlying problem, it may be possible to address that. Regular follow-up and monitoring for other health problems is necessary