The addition of doxazosin to the treatment regimen of hypertensive patients not responsive to nifedipine

Abstract

The efficacy and safety of doxazosin, a selective alpha 1-inhibitor, were assessed in hypertensive patients who failed to respond to nifedipine. Fifty patients were entered into a study that involved three phases: (1) a 2-week baseline period, (2) a 10-week period in which patients received doxazosin, 1 to 8 mg, once daily, and (3) a 4-week maintenance period. After 14 weeks, all 43 efficacy evaluable patients were considered therapy successes (sitting diastolic blood pressure either less than or equal to 90 mm Hg or greater than or equal to 10 mm Hg reduction) at a mean daily dose of 3.1 mg. Ninety-three percent achieved blood pressure control (sitting diastolic blood pressure less than or equal to 90 mm Hg) at a mean dose of 3.1 mg once daily. By the final treatment visit, sitting systolic and diastolic blood pressures of efficacy evaluable patients were reduced (p less than 0.05) by 16/18 mm Hg from a mean baseline of 157/103 mm Hg to a final value of 141/85 mm Hg. The most prevalent side effect was vertigo (six patients). Most side effects were mild or moderate and disappeared or were tolerated with continued therapy. No clinically significant laboratory changes were apparent, and no trends were observed with regard to organ systems or correlations with dose or duration of treatment. The investigators' global assessment was excellent or good for 98% of patients for both efficacy and toleration. From baseline to final visit there was a highly significant reduction of 17% (p less than 0.001) in the calculated coronary heart disease risk score, which was based on the Framingham equation.