Malegra exerts its effects by inhibiting the action of phosphodiesterase type 5 enzymes. PDE5 enzymes are responsible for the breakdown of cyclic guano sine monophosphate (camps), a chemical messenger involved in the relaxation of smooth muscle cells and dilation of blood vessels in the penis. By inhibiting PDE5, Malegra prolongs the presence of camp, thereby enhancing its vasodilator effects and promoting erectile function.