Aphrodisiac
Sildenafil is commonly and increasingly used as an aphrodisiac. Nevertheless there is no clinical evidence that it has sexual desire boosting effect, although increased ability to attain an erection may be interpreted as increased sexual arousal by users of these drugs.

Pulmonary hypertension
Sildenafil is also effective in the rare disease pulmonary arterial hypertension. It relaxes the arterial wall, leading to decreased pulmonary arterial pressure. This in turn reduces the load of the right ventricle of the heart and improves symptoms of right-sided heart failure. Because PDE-5 is primarily distributed within the arterial wall smooth muscle of the lungs and penis, sildenafil acts selectively in both these areas without inducing vasodilation in other areas of the body. Pfizer submitted an additional registration for sildenafil to the FDA, and sildenafil was approved for this indication in June 2005. The preparation is named Revatio, to avoid confusion with Viagra, and the 20 milligram tablets are white and round. Sildenafil joins bosentan and prostacyclin-based therapies for this condition.

Dosage
The drug is in sold in 3 dosages(25, 50, and 100 mg). It is very important to keep to the dosage of the medecine. For erectile dysfunction it is 25 mg to 100 mg taken once per day between 30 minutes and 4 hours before sexual intercourse.It is recommended to start with the 50 mg one and then, depending on the further state of the patient to lower or raise the dosage. The dosage for pulmonary arterial hypertension is one 20 mg tablet three times a day.The pills intended for erectile dysfunction are blue and diamond-shaped with the words "Pfizer" engraved on one side, and "VGR xx" on the other. The pills intended for pulmonary arterial hypertension are white, round, with "RVT 20" engraved on one side and "Pfizer" on the other.The cost of Viagra is about 10$ per pill.
Market structureIn 2000 Vagra sales made 90% of all erectile dysfunction fighting medecines in the world.By 2007 sales plunged due to appearance of multitude fakes and made 50% only.
Use in sports Professional sports players have been using drugs such as Viagra believe that the widening of their blood vessels will enrich their muscles, therefore enhancing their performance.