SYNOPSISBiofeedback training for vascular and neuromuscular (EMG) control has been used for the treatment of migraine, chronic muscle contraction headaches, and myofascial pain syndromes. Many patients undergoing this training are concurrently taking propranolol, a beta blocker, and/or amitriptyline, a tricyclic antidepressant which inhibits re-uptake of serotonin. There is an extreme paucity of information delineating the effects and interactions of these medications in patients learning autonomically mediated vascular control through biofeedback. In this pilot study we examined the ability of patients to learn vascular control and neuromuscular control. Four groups of patients were used: those taking no medication, those taking propranolol or amitriptyline alone, and patients using both medications. Results indicate the use of propranolol in patients learning vascular control produces a markedly increased variability in the ability of patients to control physiological parameters; this difficulty is also manifested in EMG training of patients taking only amitriptyline. Those within group variances were found to be negated by the use of both medications together. In spite of these findings, all groups did reach training criterion. In some patients the inability to easily control baseline physiological parameters may induce enough frustration to cause premature termination of training. It is postulated that the effectiveness of biofeedback training might be enhanced in patients not concurrently taking medications with autonomic effects. (Headache 24:59-69, 1984)