More robust CYP3A4 inhibitors for instance ketoconazole or itraconazole can be envisioned to obtain higher effects than seen with saquinavir. A beginning dose of twenty five mg of VIAGRA need to be thought of in patients having erythromycin or strong CYP3A4 inhibitors (such as saquinavir, ketoconazole, itraconazole) [see DOSAGE AND ADMINISTRATION,