More powerful CYP3A4 inhibitors which include ketoconazole or itraconazole may very well be anticipated to have larger results than found with saquinavir. A starting up dose of 25 mg of VIAGRA must be regarded as in people using erythromycin or potent CYP3A4 inhibitors (including saquinavir, ketoconazole, itraconazole) [see DOSAGE AND ADMINISTRATIO