A high quality ED drug called fildena 100 contains the active ingredient Sildenafil Citrate. This medicine is a prescription based medicine earlier men used to use the branded medicine Vigar for this problem which is very expensive due to which now people are using fildena 100 this medicine works like Vigar and is relatively cheaper. So people insist on using this medicine more. The effect of this medicine lasts for 4 to 5 hours, so this medicine should be used only once in a day and avoid taking the medicine more than once.