Adrenal glands

Each adrenal gland is about the size of the top part of the thumb. The outer part of the gland is called the cortex. It produces steroid hormones such as cortisol, aldosterone, and hormones that can be changed into testosterone. The inner part of the gland is called the medulla. It produces epinephrine and norepinephrine. These hormones are also called adrenaline and noradrenaline.

When the glands produce more or less hormones than normal, you can become sick. This might happen at birth or later in life.

The adrenal glands can be affected by many diseases, such as autoimmune disorders, infections, tumors, and bleeding. Some are permanent and some go away over time. Medicines can also affect the adrenal glands.

The pituitary, a small gland at the bottom of the brain, releases a hormone called adrenocorticotropic hormone (ACTH) that stimulates the adrenal cortex to make its hormones. Pituitary diseases can lead to problems with adrenal function.

Conditions related to adrenal gland problems include:

• Addison disease (adrenal insufficiency) -- an autoimmune disorder that causes the adrenal glands to not produce enough hormones
• Congenital adrenal hyperplasia -- a disorder in which the adrenal glands lack an enzyme needed to make certain hormones
• Cushing syndrome -- a disorder that occurs when the body has a high level of the hormone cortisol
• Diabetes mellitus (high blood sugar) caused by the adrenal gland making too much cortisol
• Hirsutism – a condition in which women grow excessive or unwanted hair on their faces and bodies 
• Dorsocervical fat pad – a hump on the upper back between the shoulder blades
• Hypoglycemia -- low blood sugar
• Primary aldosteronism (Conn syndrome) -- a disorder in which the adrenal gland releases too much of the hormone aldosterone
• Massive bilateral adrenal hemorrhage (Waterhouse-Friderichsen syndrome) -- the failure of the adrenal glands to function as a result of bleeding into the gland, usually associated with severe infection, called sepsis

Also, taking glucocorticoid medicines, such as prednisone, methylprednisolone, dexamethasone, and hydrocortisone, can cause adrenal gland problems.

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Nieman LK. Adrenal cortex. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 208.

Young WF. Adrenal medulla, catecholamines, and pheochromocytoma. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 209.

Updated by: Sandeep K. Dhaliwal, MD, board-certified in Diabetes, Endocrinology, and Metabolism, Springfield, VA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.