Evaluation of Autonomic Insufficiency History Symptoms suggesting autonomic insufficiency include Orthostatic intolerance (development of autonomic symptoms such as light-headedness that is relieved by sitting down) due to orthostatic hypotension or postural orthostatic tachycardia syndrome Heat intolerance Loss of bladder and bowel control Erectile dysfunction (an early symptom) Other possible symptoms include dry eyes and dry mouth, but they are less specific.