The pituitary gland sits in your brain. It is also called the master gland because it tells other glands what to do. The adrenal glands need permission from the pituitary glands to make steroids. When there are problems with the pituitary glands, they can’t give the OK signal to the adrenal glands. This “OK signal” is in the form of a hormone called the Adrenocorticotropic hormone, or simply ACTH. When the pituitary gland can’t make ACTH, the adrenal gland can’t make steroids. There are many diseases and conditions that interfere with the pituitary gland and affect ACTH production. Secondary adrenal insufficiency is less common than primary adrenal insufficiency.