| 1. Accepted major perpetrators | 2. Rejected perpetrators | 3. Unclassifiable | 4. Full table |
phenytoin is a strong inducer of CYP1A2 and CYP3A. phenytoin has not been evaluated in the literature showing its role of altering the activities of CYP2C9 and CYP2C19.
- Strong inducers: ≥ 2-fold decrease in AUC or ≥ 50% increase in clearance of in vivo CYP probe.
- Not evaluated in the literature: drugs implicated as inhibitors and inducers of CYP enzymes without reported clinical PK interaction studies.
Footnotes and References
|a.||poster found at http://www.klinikum.uni-heidelberg.de/fileadmin/medizinische_klinik/Abteilung_6/pdf/Posterpreis_VKliPha2008_Bayer.pdf|
|b.||likely to be a major inhibitor based on subjective evaluation (≥ 2-fold AUC increase or ≥ 50% decrease in clearance of in vivo CYP probe).|
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|2.||Backman JT, Granfors MT, Neuvonen PJ. Rifampicin is only a weak inducer of CYP1A2-mediated presystemic and systemic metabolism: studies with tizanidine and caffeine. European Journal of Clinical Pharmacology 2006; 62: 451-61.[PubMed]|
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|6.||Wang LS, Zhou G, Zhu B, Wu J, Wang JG, El-Aty AMA, Li T, Liu J, Yang TL, Wang D, Zhong XY, Zhou HH. St John's wort induces both cytochrome P450 3A4-catalyzed sulfoxidation and 2C19-dependent hydroxylation of omeprazole. Clinical Pharmacology & Therapeutics 2004; 75: 191-97.[PubMed]|
|7.||Ucar M, Neuvonen M, Luurila H, Dahlqvist R, Neuvonen PJ, Mjorndal T. Carbamazepine markedly reduces serum concentrations of simvastatin and simvastatin acid. European Journal of Clinical Pharmacology 2004; 59: 879-82.[PubMed]|
|8.||Robertson P, Hellriegel ET, Arora S, Nelson M. Effect of modafinil on the pharmacokinetics of ethinyl estradiol and triazolam in healthy volunteers. Clinical Pharmacology & Therapeutics 2002; 71: 46-56.[PubMed]|
|9.||Backman JT, Olkkola KT, Ojala M, Laaksovirta H, Neuvonen PJ. Concentrations and effects of oral midazolam are greatly reduced in patients treated with carbamazepine or phenytoin. Epilepsia 1996; 37: 253-57.[PubMed]|
|10.||Backman JT, Olkkola KT, Neuvonen PJ. Rifampin drastically reduces plasma concentrations and effects of oral midazolam. Clinical Pharmacology & Therapeutics 1996; 59: 7-13.[PubMed]|
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