Liquid chromatographic determination of propoxyphene and norpropoxyphene in plasma and breast milk.

A sensitive and specific high-performance liquid chromatographic (HPLC) procedure was developed for determination of propoxyphene and norpropoxyphene in plasma and breast milk. The compounds were isolated from the biological specimen by extraction, the organic phase was evaporated to dryness, and the residue was redissolved in mobile phase [acetonitrile: 0.002 M H2SO4 (1:1)].

Excretion of propoxyphene and norpropoxyphene in breast milk.

Propoxyphene (P) and norpropoxyphene (NP) excretion in breast milk was studied in six healthy nursing mothers. Concentrations of P and NP in breast milk and plasma were quantitated by an HPLC method. Plasma P t 1/2 s in mothers averaged 4.