Amphetamine is thought to inhibit monoamine oxidase, whereas the ability of amphetamine and its metabolites to inhibit different P450 isozymes and various enzymes has not been adequately elucidated. In vitro experiments with human microsomes point out insignificant inhibition of CYP2D6 by amphetamine and slight inhibition of CYP1A2, 2D6, and 3A4 by