Vilitra, like its branded version Levitra contains Vardenafil as the active pharmaceutical ingredient (API). Vardenafil belongs to a family of drugs called PDE-5 inhibitors. After oral consumption, it blocks the actions of the enzyme phosphodiesterase type 5 (PDE-5). This leads to a rise in the levels of cGMP inside the penile area. cGMP is an endogenous substance that relaxes the smooth muscles and dilation of the penile arteries. This ultimately results in a stronger penile erection. The onset of action Vardenafil is 10 minutes, while its duration of effect is five to seven hours. It has a chemical formula of C23H32N6O4S and a molar mass of 488.604 g/mol. Vardenafil is available in various doses. The usual starting dose of Vilitra is 10mg. This medication is not habit-forming. This medication should not be used by men under 18 years of age.