Metabolism of Etidocaine in Man

Abstract

1. Etidocaine and eight metabolites excreted in urine of man have been detected by g.l.c. and investigated by g.l.c.-mass spectrometry.

2. Five metabolites have been identified by comparison with authentic compounds as 2-amino-2′-butyroxylidide, 2-iV-ethylamino-2′-butyroxylidide, 2-iV-propylamino-2′-butyroxylidide, 2,6-dimethylaniline and 4-hydroxy-2,6-dimethylaniline.

3. The structure of one of the remaining three metabolites is proposed to be 2-methyl-N³-(2,6-dimethylphenyl)-5-ethyl-4-imidazolidinone.

4. The amounts of etidocaine and seven of its metabolites excreted in a 48 h urine following epidural administration to a patient have been estimated. Approx. 31% of the dose was accounted for.