Treatment of adrenal insufficiency involves taking adrenal hormone replacements, otherwise known as steroid hormones. These are usually taken as tablets by mouth. A higher dose of steroid hormones may be required when the body is experiencing physical stress, such as during periods of illness. During a more serious illness, you may need to receive injection steroids in hospital. 

Depending on the cause of adrenal insufficiency, it may be possible to eventually stop taking steroid hormone replacements in some cases. However, this should only be decided by your doctor.