What Is Addison’s Disease?

Addison's disease occurs when the adrenal glands do not produce enough of the hormone cortisol and, in some cases, the hormone aldosterone. The disease is also called adrenal insufficiency, or hypocortisolism.

Failure to produce adequate amounts of cortisol (or adrenal insufficiency) can occur for different reasons. The problem may be due to a disorder of the adrenal glands themselves (primary adrenal insufficiency) or to an inadequate secretion of ACTH by the pituitary gland (secondary adrenal insufficiency).

The symptoms of adrenal insufficiency usually begin gradually. Chronic, worsening fatigue and muscle weakness, loss of appetite, and weight loss are characteristic of the disease. Nausea, vomiting, and diarrhea occur in about 50 percent of cases. Blood pressure is low and falls further when standing, causing dizziness or fainting.

Skin changes also are common in Addison's disease, with areas of hyperpigmentation, or dark tanning, covering exposed and nonexposed parts of the body. This darkening of the skin is most visible on scars, skin folds and pressure points such as the elbows, knees, knuckles, and toes; lips; and mucous membranes.