There is considerable interest in blood pressure reactivity to psychological stressors. Because the sympathetic nervous system and the renin-angiotensin system are so responsive to stressors and are themselves the targets of many antihypertensive medications, many investigators have wondered if such medications decrease the blood pressure response to stressful stimuli. We studied 25 normotensive and 21 hypertensive men in a double-blind crossover study during which they received either placebo for 4 days or captopril (25 mg b.i.d.) for 4 days while they were hospitalized in a clinical research center. Patients were studied at resting baseline, while performing a mathematics task, and while reading out loud a disturbing newspaper article. Although captopril lowered the resting blood pressure levels, it had no effect on the amplitude of reactivity to stressors.