What are the effects of viagra?

Viagra is used to stifle the messengers of cGMP. So that a male can sustain an erection.

Side effects can include headaches, stuffy nose, impaired vision, sensitivity to light, indigestion, and the possibility of a (painful) long lasting erection

An erection that will not go away (priapism).

S udden vision loss in one or both eyes

Sudden hearing decrease or hearing loss.