The active substance sildenafil in Cenforce 100 belongs to a group of medicines named phosphodiesterase 5 inhibitors. It works by helping to widen the blood vessels of the penis, allowing blood flow while you are sexually aroused. Sildenafil Fildena 100 can only assist you to obtain an erection when you are sexually aroused. It is a state in which a man can not achieve or sustain a penis erection necessary for sexual activity. People who can't swallow a pill they can use Kamagra Oral Jelly.