Quinidine Dalfopristin

In vitro studies found quinupristin/dalfopristin inhibited the cytochrome P450 isoenzyme CYP3A4-mediated metabolism of docetaxel, tamoxifen, and terfenadine. Quinupristin/dalfopristin is predicted to raise the levels of other drugs ineluding antiarrhythmics (disopyramide, lidocaine, quinidine), antiretrovirals (such as delavirdine, indinavir, nevirapine, ritonavir), astemizole, carbamazepine, cisapride, methyl-prednisolone, paclitaxel, statins (but see Lipid regulating drugs , (p.l086)), and vinca alkaloids. More study is needed. 

---