Effect of penbutolol (Hoe 893 d) and practolol on exercise-induced angina pectoris 2 and 24 hours after a signle oral dose

Efficacy of once daily penbutolol in chronic stable angina. An objective comparison with long-acting propranolol

The effects of penbutolol (40 mg daily) and long-acting propranolol (160 mg daily) were assessed in 26 patients with chronic stable angina in a placebo-controlled randomised double-blind crossover study with 2-weekly treatment periods. In addition to conventional subjective assessment, serial multistage treadmill exercise was used to obtain objective data on drug efficacy and 24-hr ambulatory electrocardiography performed for diurnal heart rate analysis. The mean exercise time of 6.3 +/- 0.5 (SEM) min on placebo increased to 7.3 +/- 0.6 min on penbutolol (P less than 0.01) and to 7.9 +/- 0.5 min on propranolol (P less than 0.001). The pre-exercise resting heart rate was 73 +/- 2 beats/min on placebo and decreased to 63 +/- 2 beats/min on penbutolol (P less than 0.001) and 58 +/- 2 beats/min on propranolol (P less than 0.001). The maximum exercise heart rate was similarly reduced by both drugs and there was a corresponding reduction in peak exercise double product. The time-corrected maximum ST segment depression was reduced by both drugs and neither produced a delay in ST segment recovery. Both drugs effected significant reductions in ambulatory maximum hourly heart rates throughout 24 hr. The lowest observed heart rate on penbutolol was 40 beats/min and 34 beats/min on propranolol. Penbutolol is an effective antianginal agent with a profile of action similar to that of propranolol.

Comparison of once and twice daily sotalol in exercise-induced angina pectoris

The efficacy of chronic oral treatment with a total daily dose of 320 mg sotalol, given as a single or as two divided doses, was compared with placebo in a double-blind cross-over study of 12 patients with angina pectoris. Sotalol given once or twice daily significantly reduced heart rate and systolic and diastolic blood pressures at rest. The exercise heart rates were significantly decreased in both treatment groups. After sotalol 320 mg once daily, there was a greater reduction in the maximum exercise heart rate 2 h after taking the last tablet than after sotalol 160 mg b.i.d. The systolic blood pressure at the highest comparable work-load was significantly and equally reduced by sotalol both once and twice daily. Total work (watts X minutes in both sotalol treatment groups was significantly increased compared to placebo. There was no difference between the two sotalol dosage regimens. The peak plasma levels were higher after the once daily treatment, but the trough levels were similar for both regimens. No serious side effects were observed.

Penbutolol: a preliminary review of its pharmacological properties and therapeutic efficacy in hypertension and angina pectoris

Penbutolol is a non-selective beta-blocking drug with 'moderate' intrinsic sympathomimetic (partial agonist) properties, and a relatively narrow dose-response range. In many other aspects its pharmacological profile resembles that of propranolol. Significant beta-blockade, as demonstrated by reduction in heart rate during exercise in healthy subjects, persists for at least 24 hours after penbutolol administration, and thus the recommended dosage schedule in both hypertension and angina involves single daily doses (20 or 40mg daily) in most patients, with a divided dose (40mg twice daily) if a higher dose is needed. However, most angina prophylaxis studies to date have not been designed to clearly demonstrate that the beneficial effects of beta-blockade with a single dose of penbutolol extend throughout a 24-hour dosing interval. Further studies are needed to provide such evidence. As might be expected, penbutolol appears to be about as effective as usual doses of propranolol in both mild to moderate hypertension and in angina, but much of the clinical experience with the drug is in unpublished form and is thus somewhat difficult to evaluate in detail. The choice of a beta-blocking drug should be based on a knowledge of the characteristic pharmacodynamic and pharmacokinetic properties of the individual drugs within this group, and on careful consideration of how these properties might be used to benefit the individual patient. As is the case with most other beta-blocking drugs, penbutolol has some specific properties (e.g. relatively narrow dose-response range minimising the difficulty of dose titration, moderate intrinsic sympathomimetic activity) which may be used to advantage in certain patients.

Single daily dose penbutolol in the treatment of hypertension: a double blind crossover comparison with propranolol

Penbutolol is a potent long-acting non-cardioselective beta-adrenergic blocker with partial agonist activity. A double-blind cross-over comparison of penbutolol given in a single daily dose and propranolol given twice daily in the treatment of ambulant patients with moderate hypertension is described. Fourteen patients completed the study and were treated with each drug for 12 weeks. Penbutolol in daily doses of 20-120 mg and propranolol in daily doses of 80-400 mg produced similar significant reductions in both supine and erect blood pressure. Penbutolol did not reduce heart rate to the same extent as propranolol, in equivalent doses. Penbutolol appears to produce adequate control of moderate hypertension when administered once a day, and this effect appears to be equivalent to divided doses of propranolol. No serious adverse effects were reported, although one patient receiving penbutolol experienced severe eye pains at a dose of 40 mg which resolved on crossing over to treatment with propranolol.