Increased plasma conc w/ strong CYP3A4 inhibitors (eg, clarithromycin, itraconazole, ritonavir); P-gp & BCRP efflux transporters inhibitors. May increase exposure w/ moderate CYP3A4 inhibitors (eg, diltiazem, erythromycin, fluconazole); cyclosporine or quinidine. Decreased plasma conc w/ strong (eg, phenobarb, rifampicin, St. John's wort) or moderate (eg, bosentan, efavirenz, modafinil) CYP3A4 inducers. Avoid another dose of Nurtec w/in 48 hr when concomitantly administered w/ strong P-gp inhibitors (eg, cyclosporine, verapamil, quinidine); moderate CYP3A4 inhibitors (eg, fluconazole).