The symptoms of Addison's disease generally include extreme fatigue, weakness, abdominal pain, muscle and joint aches, salt craving, dizziness, nausea, vomiting, loss of appetite, and weight loss. Additionally, clinical signs such as darkening of the skin, particularly on the head, neck, back of the hands, and mucous membranes (especially the gum mucosa), low blood pressure, decreased hair in the armpit and groin regions in women, and decreased libido may also be observed.