kamagra 100 is for people suffering from erectile dysfunction or impotence. The active ingredient in this medicine is sildenafil citrate, which relaxes the muscles and helps increase blood flow to the penis. This medicine is taken 30 to 60 minutes before the sexual session. The effect of this drug lasts for 4-5 hours. It can be taken with or without food but it is better if taken on an empty stomach. Take the tablet whole, and do not chew or crush the pill. Women should not use this medicine.