Sildenafil acts as the active ingredient in the Cenforce 25mg drug. Cenforce 25 is taken sometime before intercourse. The effect of indigestion with Cenforce 25 Mg lasts for 4-5 hours. If you are suffering from a serious illness like heart disease, take the drug as advised by your doctor before taking Cenforce 25mg Take Cenforce 25 when you are truly sexually capable. Cenforce 25 is ED's best tablet.