Suhagra 100 works by increasing blood flow to the penis during sexual stimulation, helping men with ED achieve and maintain an erection. Sildenafil Citrate, the active ingredient in Suhagra 100, works by inhibiting an enzyme called phosphodiesterase type 5 (PDE5), which helps relax the muscles in the blood vessels of the penis. This relaxation allows for increased blood flow, enabling an erection when sexually aroused. The effects of Suhagra 100 can last around 4-6 hours, depending on individual factors such as metabolism, diet, and health.