Cenforce 100 typically lasts for 4 to 6 hours, depending on individual health, metabolism, and other factors like food or alcohol intake. It usually starts working within 30 to 60 minutes after consumption when taken on an empty stomach. Its active ingredient, sildenafil citrate, increases blood flow to help achieve and maintain an erection during sexual activity. While the drug does not cause a constant erection, it helps maintain one when sexually stimulated within its effective window. Effects may wear off gradually, and the body usually eliminates the drug completely in about 24 hours.