Men with erectile dysfunction can get treatment with Filagra. Its primary ingredient is sildenafil. To maintain an erection, sildenafil increases blood flow to the male genital organ during sexual excitement. This medication takes four to six hours to take effect. Take this medication orally with water and avoid breaking or chewing it. You must take Filagra as prescribed by your physician. Avoid taking this medication with alcoholic beverages or high-fat foods. Only guys who are at least eighteen years old can use this medication.