Prazosin in hypertension with and without methyldopa

The efficacy of prazosin was assessed in 21 patients with essential hypertension who failed to respond adequately to a combination of methyldopa and hydrochlorothiazide. The patients were divided randomly into two groups; in the first group prazosin was substituted for methyldopa and in the second group prazosin was added to the combination. In group 1, the average blood pressure (BP) fell from 144/102 mmHg (sitting) and 142/105 mmHg (standing) to 136/91 mmHg (sitting) and 129/91 mmHg (standing) after prazosin (17 mg) was substituted for methyldopa. The fall in the diastolic BP was statistically significant (p < 0.01). In group 2, BP fell from 146/101 mmHg (sitting) and 143/103 mmHg (standing) to 126/87 mmHg (sitting) and 118/86 mmHg (standing) when prazosin 14 mg was added to methyldopa and hydrochlorothiazide. The reductions in systolic and diastolic pressures were statistically significant (p < 0.001).