buprenorphine subdermal implant and fentanyl the two increase sedation. Keep away from or Use Alternate Drug. Restrict use to patients for whom choice treatment options are inadequateviloxazine will increase the level or effect of fentanyl by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Check. Viloxazine (a weak CYP3A4 inhibit