Adrenal insufficiency is caused by adrenal failure or impairment of the hypothalamic-pituitary-adrenal axis. The main symptoms of adrenal insufficiency are chronic fatigue, nausea, vomiting, anorexia, and weight loss. We report a case of adrenal insufficiency in a 38-year-old female. The patient complained of headache, dizziness, anorexia, and general weakness. We treated her with Iggisaengjin-tang and acupuncture. After treatment, the patient's symptoms were improved and serum cortisol levels rose to a normal range without the aid of steroid supplementation therapy. This case suggests that Korean medicine can be effective in the treatment of adrenal insufficiency, but more clinical reports are needed.