Ramachander G, Williams F D, Emele J F
J Pharm Sci. 1977 Jul;66(7):1047-8. doi: 10.1002/jps.2600660740.
A method is described for the estimation of dextrorphan, a metabolite of dextromethorphan, in plasma. The bioavailability of dextromethorphan hydrobromide after 30 mg po, as measured by the concentration of total (free and conjugated) dextrorphan in the plasma, was determined in six human volunteers with this procedure.