Research Article

The Evaluation of CP-001 (a Standardized Herbal Mixture of Houttuynia cordata, Rehmannia glutinosa, Betula platyphylla, and Rubus coreanus) for Cytochrome P450-Related Herb-Drug Interactions

Table 1

Information on the CYP-specific substrates used and the metabolites monitored in this study.

P450 isozymeMarker substrateConcentrationMetabolites monitoredQ1/Q3

CYP 1A2Phenacetin40 µMAcetaminophen152.1/110.1
CYP 2A6Coumarin2.5 µM7-OH-Coumarin162.9/106.9
CYP 2D6Dextromethorphan5 µMDextrorphan258.3/157.1
CYP 2C9Diclofenac10 µM4-OH-Diclofenac312.2/230.9
CYP 2C19(±)-Mephenytoin160 µM4-OH-Mephenytoin235/150.1
CYP 3A4Midazolam2.5 µM1-OH-Madazolam343.1/325.1
Internal standardTerfenadine472.4/436.4