Silagra 100 acts by inhibiting PDE-5 and enhancing gas (NO) action in erectile organ. The mechanism of erection of the erectile organ involves unharness of gas (NO) throughout sexual stimulation that activates the protein guanylate cyclase. This leads to multiplied levels of cyclic deoxyguanosine monophosphate (cGMP), leading to swish muscle relaxation and flow of blood to the erectile organ.