-Drugs that may decrease dasatinib plasma concentration: CYP3A4 Inducers: Drugs that induce CYP3A4 activity may decrease dasatinib plasma concentrations. In patients in whom CYP3A4 inducers (eg, dexamethasone, phenytoin, carbamazepine, rifampicin, phenobarbital) are indicated, alternative agents with less enzyme induction potential should be used. If dasatinib must be administered with a CYP3A4 inducer, a dose increase in dasatinib should be considered and approved by the principal investigator.