Sildenafil 20mg is a generic version of another branded sildenafil from Pfizer called Revatio ® . Remember that Pfizer first began evaluating sildenafil in the ’90s for high blood pressure as well as ischemic heart disease. While they rapidly switched over gears to focus on ED, they proceeded screening sildenafil in other setups. Greater than 300 million guys worldwide are expected to experience impotence by 2025. The research study reported was sponsored and also sustained by Pfizer Inc . The…