Sildenafil is actually a potent and selective inhibitor of cGMP-precise phosphodiesterase form 5 (PDE5), which can be answerable for degradation of cGMP in the corpus cavernosum. The molecular composition of sildenafil is analogous to that of cGMP and acts as a competitive binding agent of PDE5 from the corpus cavernosum, leading to a lot more cGMP