Nowadays there are effective drugs for erectile dysfunction like vardenafil, sildenafil, and Viagra. You can take Filagra for sexual problems like impotence, erectile dysfunction, and premature ejaculation. This medicine contains an ingredient called sildenafil which helps in increasing the blood flow to the penile tissues in men. The effect of this medicine lasts for 4 to 6 hours. You can take this medicine before or after food.