Viasil is a natural male enhancement drug. It has been developed by the Swiss Research Labs. It is marketed by the reputed Wolfson Berg Limited. It is a male potency formula that increases longevity and strengthens erection during sexual intercourse. By increasing sex drive it also addresses erectile dysfunction among men. Viasil can improve performance by increasing endurance and stamina. Penile erection is synonymous with male sexual arousal. It is a vascular event that is fueled by an increase in blood flow to the erectile tissues.