Cushing syndrome is a disorder that occurs when your body has a high level of the hormone cortisol.
The most common cause of Cushing syndrome is taking too much glucocorticoid or corticosteroid medicine. This form of Cushing syndrome is called exogenous Cushing syndrome. Prednisone, dexamethasone, and prednisolone are examples of this type of medicine. Glucocorticoids mimic the action of the body’s natural hormone cortisol. These drugs are used to treat many conditions such as asthma, skin inflammation, cancer, bowel disease, joint pain, and rheumatoid arthritis.
Other people develop Cushing syndrome because their body produces too much cortisol. This hormone is made in the adrenal glands.
Causes of too much cortisol are:
• Cushing disease, which occurs when the pituitary gland makes too much of the hormone adrenocorticotrophic hormone (ACTH). ACTH then signals the adrenal glands to produce too much cortisol. A pituitary gland tumor can cause this condition.
• Tumor of the adrenal gland
• Tumor elsewhere in the body that produces corticotropin-releasing hormone (CRH)
• Tumors elsewhere in the body that produce ACTH (ectopic Cushing syndrome)