Dose-dependent bioavailability of propranolol.

The pharmacokinetics of orally administered propranolol in doses of 10, 40, 80 and 160 mg was studied in eight healthy volunteers in a cross-over trial. The analytical method applied made possible a parallel determination of propranolol and of 4-OH propranolol. The dose-dependent kinetics of orally administered propranolol was demonstrated. In our study linear dependence could be established only within a dosage range of 40 mg to 160 mg. Both substances determined in plasma, propranolol as well as 4-OH propranolol, show a tendency toward non-linearity, particularly at the lower dosage range between 10 and 40 mg.