title: Single-dose pharmacokinetics of methylphenidate in CYP2D6 extensive and poor metabolizers.
abstract: Six adults phenotyped as either extensive (N = 4) or poor (N = 2) metabolizers for cytochrome P450 (CYP) 2D6 were given a 10-mg oral dose of methylphenidate (MPH) on two separate occasions with and without quinidine, a potent CYP2D6 inhibitor. Quinidine had no significant effect on the pharmacokinetics of either MPH or ritalinic acid, its major metabolite, in either group of CYP2D6 metabolizers. These data suggest a lack of involvement of CYP2D6 in the metabolism of MPH. Drugs that are inhibitors of CYP2D6 when taken concurrently with MPH should not affect its plasma concentration.
authors.affiliation: Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston 29425, USA. devanel@musc.edu
authors.forename: C L
authors.initials: CL
authors.lastname: DeVane
authors.forename: J S
authors.initials: JS
authors.lastname: Markowitz
authors.forename: S W
authors.initials: SW
authors.lastname: Carson
authors.forename: D W
authors.initials: DW
authors.lastname: Boulton
authors.forename: H S
authors.initials: HS
authors.lastname: Gill
authors.forename: Z
authors.initials: Z
authors.lastname: Nahas
authors.forename: S C
authors.initials: SC
authors.lastname: Risch
mesh_terms: D000293:Adolescent; D000328:Adult; D019540:Area Under Curve; D000697:Central Nervous System Stimulants / Q000493:pharmacokinetics*; D002853:Chromatography, Liquid; D019389:Cytochrome P-450 CYP2D6 / Q000235:genetics / Q000378:metabolism*; D065690:Cytochrome P-450 CYP2D6 Inhibitors; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D006207:Half-Life; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D008774:Methylphenidate / Q000031:analogs & derivatives / Q000097:blood / Q000493:pharmacokinetics*; D008875:Middle Aged; D010641:Phenotype; D011110:Polymorphism, Genetic; D011802:Quinidine / Q000037:antagonists & inhibitors
chemical_list: D000697:Central Nervous System Stimulants; D065690:Cytochrome P-450 CYP2D6 Inhibitors; D004791:Enzyme Inhibitors; D008774:Methylphenidate; D019389:Cytochrome P-450 CYP2D6; C009189:ritalinic acid; D011802:Quinidine