Efficacy of penbutolol and a fixed combination of penbutolol with furosemide in the treatment of hypertension.

In an open multi-centre study, 51 patients with mild to moderate hypertension were treated with either a single dose of 40 mg penbutolol per day for 8 weeks or changed over at 4 weeks due to inadequate response with penbutolol alone to a single dose (1 tablet) of a fixed combination of 40 mg penbutolol and 20 mg furosemide per day for a further 4 weeks. Thirty-six (70%) of the patients showed an adequate reduction in diastolic blood pressure to 95 mmHg or less on penbutolol alone. Of the 15 patients who did not show the desired response to penbutolol alone, 13 (86.7%) showed a satisfactory reduction in blood pressure after 4 weeks on the combination product; 2 of these patients had received 1 tablet twice daily from Week 6 of treatment. Two other patients received 1 tablet of the combination twice daily from Week 8 onwards for 2 weeks. Only 1 of them did not respond to this therapy. Blood pressure reduction and weight loss were significantly greater on the combination product than on penbutolol alone. No clinically significant changes were noted in serum potassium, glucose, creatinine or uric acid levels, and mild gastric side-effects at the beginning of treatment were reported in only 3 patients, 1 of whom was also receiving indomethacin.