title: Blood and urine concentrations of cyclizine by nitrogen-phosphorus gas-liquid chromatography.
abstract: Gas-liquid chromatography with nitrogen-phosphorus detection was used to analyze blood and urine from a volunteer who ingested 50 mg of cyclizine hydrochloride. A peak blood cyclizine concentration of 69 ng/mL was observed 2 hr after drug administration, and the levels declined thereafter in a biphasic manner, with estimated half-lives of 7 and 24 hr for the early and late phases, respectively. The peak urine cyclizine concentration of 12.5 ng/mL was achieved at 4 hr after administration; only 0.01% of the dose was excreted in the 24 hr urine. Norcyclizine was not observed in blood or urine; however, the detectability of the method for this metabolite is poor relative to the parent drug.
mesh_terms: D002849:Chromatography, Gas / Q000379:methods; D003501:Cyclizine / Q000031:analogs & derivatives / Q000032:analysis* / Q000097:blood / Q000652:urine; D006801:Humans; D009584:Nitrogen; D010758:Phosphorus
chemical_list: D010758:Phosphorus; C029632:norcyclizine; D009584:Nitrogen; D003501:Cyclizine