More or less patients experient a sudden passing of approximately or completely of their visual sensation afterwards they took Viagra or early medications that are like to Viagra. It is not known if the visual sense expiration was caused by the medication. If you receive a sudden exit of visual sensation while you are taking sildenafil, forebode your doctor immediately. Do not aim whatsoever Thomas More doses of Viagra or standardized medications such as Cialis (Cialis) or vardenafil (Levitra)...