Primary adrenal cortical insufficiency is a relatively rare disorder also known as Addison disease. It occurs when the adrenal cortex layers are destroyed by autoimmune disorder, tuberculosis, metastatic carcinomas, hemorrhage, infections, toxins, or certain medications (for example, ketoconazole or mitotane). Secondary adrenal insufficiency may be caused by hypopituitarism, surgical removal of the pituitary gland, or, more commonly, sudden cessation of long-term, high-dose glucocorticoid therapy.