Ibuprofen interferes with the efficacy of antihypertensive drugs. A randomized, double-blind, placebo-controlled trial of ibuprofen compared with acetaminophen.

<bold>Study Objective: </bold>To assess the effects of ibuprofen on blood pressure control in patients being treated with antihypertensive drugs.<bold>Design: </bold>Randomized, blinded, placebo-controlled, parallel trial of ibuprofen compared with acetaminophen and with placebo in 3-week treatment periods.<bold>Setting: </bold>A general internal medicine clinic at a university hospital.<bold>Patients: </bold>Forty-five patients with essential hypertension controlled by treatment with at least two antihypertensive drugs were enrolled. Of these, 41 completed the study; treatment was discontinued in 3 of the 15 patients in the ibuprofen group due to breakage of the drug capsules, and after randomization in 1 of the 14 patients in the placebo group due to unstable angina. All 15 patients in the acetaminophen group completed the study.<bold>Interventions: </bold>All previous antihypertensive regimens were continued. During the 3-week treatment, ibuprofen, 400 mg, was administered orally every 8 hours; acetaminophen, 1 g, orally every 8 hours; or placebo, 2 capsules, orally every 8 hours.<bold>Measurements and Main Results: </bold>In the ibuprofen group, the mean increase from baseline after 3 weeks of treatment was significant in the average supine diastolic blood pressure (6.4 mm Hg; 95% confidence interval [CI], 1.05 to 11.75; p = 0.0239); supine mean arterial pressure (6.6 mm Hg; 95% CI, 1.25 to 11.95; p = 0.0205); and sitting mean arterial pressure (5.8 mm Hg; 95% CI, 1.57 to 10.04; p = 0.0123). The mean increase in blood pressure variables in the ibuprofen group was significantly different compared with the mean increase in the variables in the placebo group after 3 weeks of treatment: supine systolic blood pressure (7.1 mm Hg compared with -4.5 mm Hg; 95% CI for the difference in means, 2.5 to 20.6; p = 0.0133); supine diastolic pressure (6.4 mm Hg compared with 0.0; 95% CI for difference in means, 0.87 to 12.4; p = 0.0250); supine mean arterial pressure (6.6 mm Hg compared with -1.5; 95% CI for difference in means, 2.0 to 14.2; p = 0.0110); sitting systolic pressure (6.8 mm Hg compared with -3.7; 95% CI for difference in means, 2.0 to 19.0; p = 0.0169); sitting diastolic pressure (5.3 mm Hg compared with -1.1; 95% CI for difference in means, 0.76 to 12.1; p = 0.0273); and sitting mean arterial pressure (5.8 mm Hg compared with -2.0; 95% CI for difference in means, 1.5 to 14.1; p = 0.0169).(ABSTRACT TRUNCATED AT 400 WORDS) [ABSTRACT FROM AUTHOR]