ED (erectile dysfunction) is a condition when a man has problems getting or maintaining an erection long enough for having a sexual intercourse. It usually happens when not enough blood flows to the penis. Viagra is a highly efficient drug intended to treat this condition allowing men with such problems to continue with their normal life. Before you start taking Viagra inform your doctor of any particular medical conditions you have to make sure they do not interfere with your treatment.
If you are using other drugs a dose adjustment may be required or an alternative to Viagra needs to be found: bosentan, imatinib, cimetidine, diclofenac, conivaptan, rifampin, enoxacin, isoniazid, an antibiotic (clarithromycin, clotrimazole, erythromycin, ketoconazole, or voriconazole), an antidepressant (nefazodone), heart or blood pressure medication (diltiazen, doxazosin, nicardipine), and HIV/AIDS medicine. Sudden vision loss is also one for the concerns when taking Viagra - this is a very rare complication that is still not very well studied. It may not be entirely attributed to Viagra, but also a number of other factors, such as age and lifestyle. Vision loss is most often reported by people older than 50, smokers, people with high cholesterol and high blood pressure problems, as well as those who already had some eye problems before.