The identification of eight hydroxylated metabolites of etidocaine by chemical ionization mass spectrometry.

1. Eight hydroxylated metabolites of etidocaine have been identified in urine of man by g.l.c.-chemical ionization mass spectrometry, using methane and a mixture of methane and deuterium oxide as reactant gases. 2. The metabolites identified were N-(2,6-dimethyl-3- and 4-hydroxyphenyl-)-2-(N,N-ethylpropylamino)butyramides, N-(2,6-dimethyl-3- and 4-hydroxyphenyl)-2-aminobutyramides, N-(2,6-dimethyl-3- and 4-hydroxyphenyl)-2-(N-ethylamino)butyramides, and N-(2,6-dimethyl-3- and 4-hydroxyphenyl)-2-(N-propylamino)butyramides. 3. The eight metabolites represent about 10% of the oral dose of etidocaine.