Biotransformation and urinary excretion of 4-substituted amphetamines in pregnant mice.

The urinary elimination of 4-hydroxyamphetamine (PHA) and a series of homologous 4-alkoxy-substituted amphetamines and their metabolites was examined after single and multiple oral administration to pregnant and non-pregnant mice. The metabolic profile and extent of biotransformation in a series of alkoxy analogues were affected by the size of the alkoxy side chain, multiple dosing and pregnancy. There were increased recoveries of both the substrate and the conjugated derivative of PHA during gestation. The major metabolic routes observed were O-dealkylation, conjugation, and aliphatic hydroxylation of the propoxy side chain. There was some evidence of oxidative deamination. Pregnancy did not alter the profile of the major metabolites detected by GLC and NMR spectroscopy.