Fildena is a brand of medication used for the treatment of erectile dysfunction (ED) in men. It contains the active ingredient sildenafil citrate, which is a phosphodiesterase type 5 (PDE5) inhibitor. Sildenafil works by increasing blood flow to the penis during sexual stimulation, facilitating the ability to achieve and maintain an erection.  The duration of action of Fildena online is typically around 4 to 6 hours. Sexual stimulation is necessary for the medication to be effective. Effectiveness: Fildena is effective in many men with ED. Individual responses may vary.