Viagra (sildenafil citrate) is supposed to be used by male patients that find it impossible to have sex because of insufficient erections. This drug has been specially designed for the needs of patients that are unable to have se, this inability being caused by a number of physical or psychological factors. You will need to make sure you always take Viagra as prescribed. In case you purchased this medicine online, read the label carefully before starting the treatment to see if there is anything you need to know before taking the first dose. If you have any medical conditions as heart rhythm problems, leukemia, condition of the eye, liver disease, high or low blood pressure, physical deformity of the penis, congestive heart failure, a recent history of a heart attack or stroke, kidney disease, sickle cell anemia, hemophilia, multiple myeloma, stomach ulcer, or coronary artery disease, you may not be able to use Viagra, or a dose adjustment will be required. Viagra is not a cure, rather than a treatment. This drug is supposed to be taken regularly on the when needed bases for you to benefit form the treatment as much as possible. You will also need to observe the dose you have been prescribed, as otherwise there is a risk you take too much of it.