Actilis is actively composed of Tadalafil, which is a PDE5 inhibitor drug. Inhibiting the enzyme; stops the degradation of the cGMP vasodilator. As soon as the level of cGMP increases, it works to dilate the blood vessels; next, nitric oxide helps to increase blood flow towards the male organ that results in an erection. Actilis pill works within 60 minutes. Sexual stimulation is necessary to attain an erection.