“…The in vivo induction is represented by the decrease in AUC for a CYP3A probe drug, administered before and after treatment with the inducing agent. The in vivo probes used for the correlation were midazolam for rifampicin (Backman et al, 1996a(Backman et al, , 1998, phenytoin (Backman et al, 1996b), carbamazepine (Backman et al, 1996b), and hyperforin (St. John's wort) (Wang et al, 2001); verapamil for phenobarbital (Rutledge et al, 1988) and sulfinpyrazone (Wing et al, 1985); terfenadine for troglitazone (Loi et al, 1998); and triazolam for dexamethasone (Villikka et al, 1998). These probe drugs are moderate or high clearance drugs (Greenblatt et al, 1998;Wong et al, 1998;Lin, 2006), and the clearance and bioavailability are dependent on CYP3A4 metabolism.…”