Cenforce 100 mg contains sildenafil citrate, the same active ingredient used in many erectile dysfunction medicines. Its duration of action is generally similar across brands, including Sildenafil. After taking Cenforce 100 mg, the onset of effect usually begins within 30 to 60 minutes. The strongest effect (peak action) typically occurs around 1 to 2 hours after ingestion. From that point, the ability to Cenforce 100 mg an erection gradually declines over time. In most users, the effective duration of action is about 4 to 6 hours. During this window, sexual stimulation can more easily produce and maintain an erection. However, it does not mean a continuous erection; the medicine only works when there is sexual arousal. The half-life of sildenafil is around 4 hours, which explains why its effects slowly wear off rather than stopping suddenly. After about 6 hours, most of the noticeable effect is significantly reduced, although small amounts may remain in the body longer. Factors like high-fat meals, alcohol intake, age, liver/kidney function, and other medications can shorten, delay, or weaken its effect.