PHARMACOKINETICS OF BUPROPION AND ITS METABOLITES IN CIGARETTE SMOKERS VERSUS NONSMOKERS

Bupropion is an antidepressant agent that is also effective as an aid to quit cigarette smoking. A single 150-mg tablet of sustained-release bupropion hydrochloride was administered to two groups of volunteers, cigarette smokers and nonsmokers, who were matched for race, gender, body frame, age, and weight. Pharmacokinetic parameters were calculate d for bupropion, and three major metabolites (hydroxybupropion and the aminoalcohol isomers, threohydrobupropion and erythrohydrobupropion, expressed as a composite total). Mean (+/- SD) values of area under th e concentration-time curve from time 0 extrapolated to infinity (AUC(0 -infinity)) maximum concentration (C-max), time to reach C-max (t(max) ), and half-life (t(1/2)) of bupropion in smokers and nonsmokers, resp ectively, were 1,164 +/- 220 ng.hr/mL and 1,161 +/- 292 ng.hr/mL; 144 +/- 28 ng/mL and 143 +/- 39 ng/mL; 3.00 +/- 0.50 hours and 2.88 +/- 0. 49 hours; and 19 +/- 5 hours and 18 +/- 3 hours. No clinically signifi cant differences between smokers and nonsmokers or between male and fe male volunteers were observed for the pharmacokinetics of bupropion or its metabolites. The absence of pharmacokinetic differences indicates that dosage adjustments are not necessary when bupropion is prescribe d to male and female cigarette smokers.