AN 351 pill is used to treat male impotence. It belongs to the generic brand Sildenafil. The main ingredient in AN 351 white round pill is Sildenafil citrate, gradually it is a heal ED in males and also useful for males and females for Pulmonary hypertension. It contains the enzyme phosphodiesterase-5 (PDE-5) inhibitors which increase the blood flow level in the body.