Sildenafil is the active ingredient of kamagra gel, a popular medicine. When a man has a sex problem, he should take kamagra. The best medicine is then employed to solve the problem. This medicine should be given one hour before intercourse. Its effects remain for about 4-5 hours after you take it. Before taking kamagra, it is best to visit a doctor. Which is commonly used. Tablet is one of the greatest ED tablets.