Fildena 120 mg contains a comparative substance compound like other classes of Fildena drugs, which is Sildenafil Citrate. The main activity of the drug is to limit the protein phosphodiesterase within the divider of blood vessels leading to the penis. When the amount of PDE5 protein is increased, cyclic monophosphate decreases. This cyclic monophosphate is responsible for dilating the courses provided by the penis. When cGMP accumulates, the progression of the blood expands, which helps in a unique way in cases of incitement.