Cenforce 100 mg works by inhibiting the enzyme phosphodiesterase type 5 (PDE5). PDE5 is responsible for breaking down cyclic GMP, a compound that helps relax the blood vessels in the penis, allowing for increased blood flow. By inhibiting PDE5, Cenforce 100 mg allows cyclic GMP to remain in the bloodstream, enhancing blood flow and helping men with ED achieve an erection when sexually aroused.