title: Effects of daily ingestion of cranberry juice on the pharmacokinetics of warfarin, tizanidine, and midazolam--probes of CYP2C9, CYP1A2, and CYP3A4.
abstract: Case reports suggest that cranberry juice can increase the anticoagulant effect of warfarin. We investigated the effects of cranberry juice on R-S-warfarin, tizanidine, and midazolam; probes of CYP2C9, CYP1A2, and CYP3A4. Ten healthy volunteers took 200 ml cranberry juice or water t.i.d. for 10 days. On day 5, they ingested 10 mg racemic R-S-warfarin, 1 mg tizanidine, and 0.5 mg midazolam, with juice or water, followed by monitoring of drug concentrations and thromboplastin time. Cranberry juice did not increase the peak plasma concentration or area under concentration-time curve (AUC) of the probe drugs or their metabolites, but slightly decreased (7%; P=0.051) the AUC of S-warfarin. Cranberry juice did not change the anticoagulant effect of warfarin. Daily ingestion of cranberry juice does not inhibit the activities of CYP2C9, CYP1A2, or CYP3A4. A pharmacokinetic mechanism for the cranberry juice-warfarin interaction seems unlikely.
authors: Department of Clinical Pharmacology, University of Helsinki, and Helsinki University Central Hospital, Helsinki, Finland. jari.lilja@hus.fi
authors: J J
authors: JJ
authors: Lilja
authors: J T
authors: JT
authors: Backman
authors: P J
authors: PJ
authors: Neuvonen
mesh_terms: D000328:Adult; D000925:Anticoagulants / Q000737:chemistry / Q000493:pharmacokinetics; D019540:Area Under Curve; D001189:Aryl Hydrocarbon Hydroxylases / Q000378:metabolism*; D001628:Beverages; D003000:Clonidine / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D018592:Cross-Over Studies; D019388:Cytochrome P-450 CYP1A2 / Q000378:metabolism*; D065729:Cytochrome P-450 CYP2C9; D051544:Cytochrome P-450 CYP3A; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D005260:Female; D018565:Food-Drug Interactions; D006207:Half-Life; D006801:Humans; D008297:Male; D008874:Midazolam / Q000493:pharmacokinetics*; D013237:Stereoisomerism; D029799:Vaccinium macrocarpon; D014859:Warfarin / Q000737:chemistry / Q000493:pharmacokinetics*
chemical_list: D000925:Anticoagulants; D014859:Warfarin; C023754:tizanidine; D003577:Cytochrome P-450 Enzyme System; C450260:CYP2C9 protein, human; D065729:Cytochrome P-450 CYP2C9; D001189:Aryl Hydrocarbon Hydroxylases; C504573:CYP1A2 protein, human; D019388:Cytochrome P-450 CYP1A2; D051544:Cytochrome P-450 CYP3A; C510163:CYP3A4 protein, human; D003000:Clonidine; D008874:Midazolam