Sildenafil Super Active is the fastest to absorb and longest to stay active version of Viagra. This pill, which is the newest version of Viagra, represents the fourth generation of phosphodiesterase inhibitors which work by restraining a chemical in the man's body called PDE5, responsible for reducing the flow of blood in a human's body, and hence, allowing erection to occur with sexual stimulation. Sildenafil Citrate Super Active should be taken no more than once daily and stays effective for up to 9 hours. Active ingredient: Sildenafil.