Cenforce 25 mg is marketed as containing sildenafil citrate 25 mg, a PDE5 inhibitor used to treat erectile dysfunction (ED). Sildenafil works by increasing blood flow to the penis during sexual stimulation, helping a man achieve and maintain an erection. A 25 mg dose is considered a lower sildenafil dose than the commonly used 50 mg starting dose. It may be appropriate for some men, particularly when a lower dose is recommended because of age, other medicines, or sensitivity to side effects. It should generally be taken about 30–60 minutes before sexual activity and not more than once in 24 hours.