Viagra (sildenafil citrate) is a highly efficient drug you can use for the treatment of male impotence, or erectile dysfunction. You are not supposed to take Viagra unless you have been told so b your doctor. Viagra is a medicine that belongs to the class of PDE5 inhibitors. Its effects are based on stimulating more blood flow into the tissues of the penis therefore making it possible for you to enjoy your treatment and hard erections you can get as a result. Viagra patients do not only get erections sufficient for attempting sexual intercourse, they are also able to maintain it throughout the intercourse. Before you start taking Viagra, make sure you do not have a history of a stroke, abnormal blood pressure, stomach ulcer, bleeding disorder, coronary artery disease, blood cell disorder, heart attack, kidney disease, or any other particular medical conditions that may require a dose adjustment or prevent you from taking Viagra safely. This drug is sold online and can be purchased with a lot less money spent. You will need to make sure you get your Viagra from only best drug suppliers, as that means you will always get the quality of service you expect.