What causes adrenal gland problems?

Many causes: "adrenal problems" is a very broad question. Your adrenal produces hormones, including cortisol and adrenaline. We need these hormones to sustain life; they are increased in response to stress. Adrenal failure can be from autoimmunity; adrenal overactivity from tumors. Alternative practitioners often allege “adrenal fatigue” from chronic stress. See an endocrinologist for adrenal problems.