The adrenal glands are two triangle-shaped glands, one gland is located on top of each kidney.
Each adrenal gland is about the size of the thumb. The outer part of the gland is called the cortex. It produces steroid hormones such as cortisol, aldosterone, and testosterone. The inner part of the gland is called the medulla. It produces epinephrine and norepinephrine, which are also called adrenaline and noradrenaline.
When the glands produce more or less hormones than your body needs, you can become sick.
The adrenal glands can be affected by many diseases, such as autoimmune disorders, infections, tumors, and bleeding, including:
Stewart PM, Krone NP. The adrenal cortex. In: Melmed S, Polonsky KS, Larsen PR, Kronenberg HM, eds. Williams Textbook of Endocrinology. 12th ed. Philadelphia, Pa: Elsevier Saunders; 2011:chap 15.
Brent Wisse, MD, Associate Professor of Medicine, Division of Metabolism, Endocrinology & Nutrition, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Bethanne Black, and the A.D.A.M. Editorial team.