Quantitative determination of dextromethorphan and three metabolites in urine by reverse-phase high-performance liquid chromatography

J Pharm Sci. 1984 Jan;73(1):24-9. doi: 10.1002/jps.2600730107.


A high-performance liquid chromatographic (HPLC) method for the quantitation of dextromethorphan (I) and its three metabolites, dextrorphan (II), 3-hydroxy-9 alpha,13 alpha,14 alpha-morphinan (III), and 3-methoxy-9 alpha,13 alpha,14 alpha-morphinan (IV), in urine was developed. For the analysis of nonconjugated compounds, urine samples at pH 11-11.5, containing 3-methoxy-17-methyl-10-oxo-9 alpha,13 alpha,14 alpha-morphinan as an internal standard, were applied to an extraction column, and the compounds were eluted with 10% n-butyl alcohol-hexane. The organic eluant was extracted with 0.1 M HCl, and an aliquot of the acidic extract was analyzed by HPLC utilizing a 5-micron phenyl column (25 X 0.46-cm i.d.) with a mobile phase of 10 mM potassium phosphate-acetonitrile (45:55, pH 4.0); the column effluent was monitored by UV detection at 280 nm. Free and conjugated metabolites in the enzyme-treated urine were analyzed by selective extraction of I and IV with hexane from urine samples at pH greater than 12 and extraction of II and III with 10% n-butyl alcohol-hexane from urine samples at pH 11-11.5. The minimum quantifiable levels of I-IV ranged from 0.017 to 0.09 micrograms of base/mL and from 0.11 to 0.21 micrograms of base/mL in nonhydrolyzed and hydrolyzed urine, respectively.

MeSH terms

  • Chromatography, High Pressure Liquid / methods
  • Dextromethorphan / metabolism*
  • Dextromethorphan / urine
  • Dextrorphan / urine
  • Humans
  • Hydrogen-Ion Concentration
  • Levorphanol / analogs & derivatives*


  • Dextrorphan
  • Levorphanol
  • Dextromethorphan