title: Studies on the human metabolism and the toxicologic detection of the cough suppressant dropropizine in urine using gas chromatography-mass spectrometry.
abstract: Studies are described on the metabolism and the toxicologic analysis of the nonopioid cough suppressant dropropizine [R,S-3-(4-phenyl-1-piperazinyl)1,2-propandiol, DRO] in human urine using gas chromatography-mass spectrometry (GC-MS). The metabolism studies showed that DRO was metabolized in humans mainly by hydroxylation of the aromatic ring, by N-dealkylation of the parent drug and of the hydroxyl-metabolite to the corresponding N-phenylpiperazines, and by degradation of the piperazine moiety. The authors' systematic toxicologic analysis (STA) procedure using full-scan GC-MS after acid hydrolysis, liquid-liquid extraction, and microwave-assisted acetylation allowed the unambiguous detection of DRO and its above-mentioned metabolites in human urine up to about 32 hours after intake of a single common therapeutic dose. The target analytes were found to be the parent compound DRO (earlier phase of excretion) and the hydroxylated metabolite para-hydroxy-DRO (later phase of excretion). Both allowed unambiguous detection of an intake of DRO and also differentiation from other phenylpiperazine derivatives.
authors.affiliation: Department of Experimental and Clinical Toxicology, Institute of Experimental and Clinical Pharmacology and Toxicology, University of Saarland, D-66421 Homburg (Saar), Germany.
authors.forename: Roland F
authors.initials: RF
authors.lastname: Staack
authors.forename: Denis S
authors.initials: DS
authors.lastname: Theobald
authors.forename: Hans H
authors.initials: HH
authors.lastname: Maurer
mesh_terms: D000996:Antitussive Agents / Q000378:metabolism* / Q000652:urine*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D008297:Male; D010879:Piperazines / Q000378:metabolism; D011409:Propylene Glycols / Q000378:metabolism* / Q000652:urine*
chemical_list: D000996:Antitussive Agents; D010879:Piperazines; D011409:Propylene Glycols; C031503:phenylpiperazine; C035916:dipropizine