Steady state relative bioavailability and pharmacokinetics of oral propranolol in black and white North Americans

摘要

AbstractThe steady state bioavailability and pharmacokinetics of propranolol over two consecutive dosing intervals were investigated in 18 black and 10 white normal volunteers following the administration of 20 mg of a test and reference oral dosage form, respectively, every 6h. There were no differences (p>0.05) between dosage forms in the mean (n= 28) area under the plasma concentration‐time curve (AUC), maximum plasma concentration (Gmax) or time to Gmax(tmax) for propranolol or its active metabolite, 4‐hydroxypropranolol. However, as a group blacks had lower plasma concentrations of propranolol and 4‐hydroxypropranolol than whites. The mean AUC and Cmaxfor propranolol during the second dosing interval (AUC‐2 and Cmax‐2, respectively) were significantly (p0.05) in tmax. The mean AUC and Cmaxfor the 4‐hydroxylated metabolite during both dosing intervals were significantly (p0.05) in each racial group. There were no substantial changes in heart rate or blood pressure in blacks or whites following propranolol administration. These data suggest that for oral propranolol, blacks have different absorption and disposition characteri