Kamagra 100mg tablets are used to treat erectile dysfunction (impotence) in men, which is inability to achieve or maintain a hard erect penis suitable for sexual activity, due to insufficient blood flow into the penis. Kamagra 100mg tablets relax the blood vessels in the penis increasing blood flow and causing an erection, which is the natural response to sexual stimulation. However, Kamagra 100mg tablets will only work if you are sexually aroused.