If there is normal function of the testes and ovaries, the physiologic effects from decreased production of the adrenal sex hormones are minor. The disease may occur as either a primary or a secondary deficit in hormone production.
Primary insufficiency is thought to be due to an autoimmune adrenalitis.
Causes include tubercular infection, fungal infections, amyloidosis, and nonsecreting tumors of the adrenal cortex. Underfunctioning of the pituitary gland, surgical removal, and certain tumors of the gland eventually result in a decrease or total absence of ACTH, the hormone that triggers the release of hormones from the adrenal cortex. Serious and potentially life-threatening problems associated with Addison's disease are fluid and electrolyte imbalance and profound hypoglycemia. The patient experiences generalized malaise and muscular weakness, muscle pain, orthostatic hypotension, and vulnerability to cardiac arrhythmias. Deficiency of cortisol adversely affects blood sugar levels, causing hypoglycemic reactions.