Whenever i see adult movies some liquid starts coming out of my penis. i have used viagra (sildenafil) for 6 months. is this why?

The : The "liquid" you are referring to is probably pre-ejaculate. This often occurs when the penis is erect before a full ejaculation takes place; the pre-ejaculate merely consists of seminal fluid. On the other hand, to be safe i would recommend that you are tested for std's (sexually transmitted diseases) often times gonorrhea or chlamydia etc. Can cause a discharge from the penis. Please re-submit another question if you have additional issues/concerns. Good luck.

Sexual excitement: will often cause some pre-ejaculate in males just like women can experience lubrication with stimulation. This can occur with/ without viagara. If the discharge occurs at other times as well, it is wise to get checked for infection.