Sildenafil
Dosing in kidney impairment
Renal Impairment No dose adjustment is required for mild (CLcr=50-80 mL/min) and moderate (CLcr=30-49 mL/min) renal impairment. In volunteers with severe renal impairment (Clcr<30 mL/min), sildenafil clearance was reduced, resulting in higher plasma exposure of sildenafil (~2 fold), approximately doubling of C max and AUC.
A starting dose of 25 mg should be considered in patients with severe renal impairment [see Dosage and Administration and Clinical Pharmacology ].
Dosing in liver impairment
Hepatic Impairment In volunteers with hepatic impairment (Child-Pugh Class A and B), sildenafil clearance was reduced, resulting in higher plasma exposure of sildenafil (47% for C max and 85% for AUC). The pharmacokinetics of sildenafil in patients with severely impaired hepatic function (Child-Pugh Class C) have not been studied.
A starting dose of 25 mg should be considered in patients with any degree of hepatic impairment [see Dosage and Administration and Clinical Pharmacology ].