title: Patient-controlled analgesia (PCA) with codeine for postoperative pain relief in ten extensive metabolisers and one poor metaboliser of dextromethorphan.
abstract: Postoperative pain relief with codeine was evaluated in 11 women undergoing hysterectomy. Patient-controlled analgesia (PCA) was used to administer codeine. After the study the patients were phenotyped with respect to the O-demethylation of dextromethorphan (cytochrome P4502D6 polymorphism). Ten were extensive metabolisers and one a poor metaboliser. There was a nine-fold variation in the minimum plasma concentration of codeine consistent with pain relief (40-350 ng ml-1). Two patients did not experience any effect of codeine, one of whom was a poor metaboliser of dextromethorphan, confirmed by genotyping. In the other nine patients the effective dose of codeine varied from 4.8-25.3 mg h-1.
authors.affiliation: Department of Clinical Pharmacology, Akademiska Hospital, Uppsala, Sweden.
authors.forename: K
authors.initials: K
authors.lastname: Persson
authors.forename: S
authors.initials: S
authors.lastname: Sjöström
authors.forename: I
authors.initials: I
authors.lastname: Sigurdardottir
authors.forename: V
authors.initials: V
authors.lastname: Molnár
authors.forename: M
authors.initials: M
authors.lastname: Hammarlund-Udenaes
authors.forename: A
authors.initials: A
authors.lastname: Rane
mesh_terms: D000328:Adult; D000368:Aged; D016058:Analgesia, Patient-Controlled / Q000379:methods*; D003061:Codeine / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000627:therapeutic use*; D019389:Cytochrome P-450 CYP2D6; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics*; D003915:Dextromethorphan / Q000378:metabolism; D005260:Female; D005838:Genotype; D006801:Humans; D008875:Middle Aged; D006899:Mixed Function Oxygenases / Q000235:genetics*; D010149:Postoperative Pain / Q000188:drug therapy*; D010641:Phenotype
chemical_list: D003915:Dextromethorphan; D003577:Cytochrome P-450 Enzyme System; D006899:Mixed Function Oxygenases; D019389:Cytochrome P-450 CYP2D6; D003061:Codeine