How to know either it's from adrenal or pituitary gland that cause my hypocortisolism mri pituitary normal. acth level low.h/o exogenous steroid 2010.

Stimulate adrenals: Have your doctor do an adrenal stimulation test to check your adrenal response. Acth levels are often inaccurate and frequently not diagnostic. If you're on cortisone replacement already, it doesn't make much difference what the cause is, however your pituitary function can be analyzed one hormone at a time. Check w/an endocrinologist.