Phosphodiesterase type 5 (PDE5) is inhibited by the active ingredient in Tadagra 60mg, tadalafil. This inhibition contributes to a boost in cyclic guanosine monophosphate (cGMP), which causes the blood vessels of the penis to expand. It will improve blood flow to the penile region and aid in achieving and sustaining erection. To obtain an erection, one has to be sexually motivated.