If you are using other drugs an amount modification could be required or a choice to Viagra has to be located: bosentan, imatinib, cimetidine, diclofenac, conivaptan, rifampin, enoxacin, isoniazid, an antibiotic (clarithromycin, clotrimazole, ketoconazole, erythromycin, or voriconazole), an antidepressant (nefazodone), heart or blood pressure medicine (diltiazen, doxazosin, nicardipine), and HIV/AIDS medicine.

Viagra is not supposed to be incorporated with alcoholic beverages, grapefruit juice and dish very high in fatty tissue as it may become less effective or give you undesirable sensations.