Aromatic ring oxidation of N-n-butylamphetamine is enhanced in the rat by prior treatment with quinidine.

Prior administration of quinidine is known to reduce aromatic oxidation of amphetamine and its analog methoxyphenamine by inhibiting the cytochrome P450IID6 results in isozyme. In contrast, it is now shown that prior administration of quinidine results in a significant increase in the aromatic oxidation of N-n-butylamphetamine in rat, suggesting that the P450IID6 isozyme is not involved in this metabolic reaction.