title: Interindividual dose/concentration relationship for methadone in hair.
abstract: Hair samples were collected from 60 patients receiving long-term methadone maintenance: 50 were taking the drug orally and 10 were receiving the drug by intravenous injection. The amount of methadone present in the hair samples was measured using methanolic extraction, derivatization of the extracts with MTBSTFA, followed by electron impact gas chromatography-mass spectrometry operating in selected ion monitoring mode. The limit of quantitation for the assay was 0.4 ng/mg hair. The dose/concentration relationship for methadone in hair was investigated. No interindividual correlation between prescribed dose and concentration of methadone in hair was observed.
authors.affiliation: Toxicology Unit, Imperial College Faculty of Medicine, St. Dunstan's Road, London, England W6 8RP. s.paterson@ic.ac.uk
authors.forename: Sue
authors.initials: S
authors.lastname: Paterson
authors.forename: Rosa
authors.initials: R
authors.lastname: Cordero
authors.forename: Mike
authors.initials: M
authors.lastname: McPhillips
authors.forename: Suzannah
authors.initials: S
authors.lastname: Carman
mesh_terms: D004305:Dose-Response Relationship, Drug; D008401:Gas Chromatography-Mass Spectrometry; D006197:Hair / Q000737:chemistry*; D006801:Humans; D008691:Methadone / Q000032:analysis*; D009294:Narcotics / Q000032:analysis*; D015813:Substance Abuse Detection / Q000379:methods*
chemical_list: D009294:Narcotics; D008691:Methadone