, is associated with increased
plasma levels of sildenafil (see DOSAGE AND ADMINISTRATION). Both sildenafil ... sildenafil clearance and inducers of these isoenzymes may increase sildenafil
clearance.
In vivo studies:
Cimetidine
(800 mg), a nonspecific CYP inhibitor, caused a 56% increase in
plasma sildenafil concentrations when ... sildenafil clearance when it was coadministered with CYP3A4 inhibitors
(such as ketoconazole, erythromycin, or
cimetidine
) (see DOSAGE AND
ADMINISTRATION).
In another study in healthy male volunteers, coadministration with