Let’s begin at the beginning. Corticosteroids, as the name suggests, are produced in the adrenal cortex. There are 2 types:  Glucocorticosteroids (e.g. cortisol) These are the ones we usually refer to as steroids.  Mineralocorticosteroids (e.g. aldosterone.) The adrenal also produces epinephrine, but for now, our focus is limited to the glucocorticosteroids. Cortisol is produced in the zona fasciculata of the adrenal glands and represents 95% of all glucocorticoid secretion. The constant, basal secretion of cortisol varies diurnally and also responds to stress and increased ACTH from the pituitary.