Fildena 100 mg is one of the first and most popular male enhancement pills. It is used in the treatment of erectile dysfunction or impotence in adults. Sildenafil citrate works by increasing the blood flow to the male penis and maintaining it by giving strength to the erection. Fildena 100 is effective for 5-6 hours. Take the tablet whole without chewing or crushing it. This medicine is a prescription pill so take it as per the doctor's recommendation.