Outcomes of Other Medication on VIAGRA Sildenafil metabolism is principally mediated by CYP3A4 (major route) and CYP2C9 (minimal route). Thus, inhibitors of those isoenzymes may reduce sildenafil clearance and inducers of such isoenzymes may raise sildenafil clearance.Viagra isn’t accepted for use in women.* It’s not recognized no matter if it�