Fildena pills is a medication used to treat erectile dysfunction in men. It contains sildenafil citrate, an inhibitor of phosphodiesterase type 5. If you're taking this for sex, take it at least 30 to 60 minutes before engaging in sexual activity. There may be side effects, but only if you don't follow your doctor's advice. The medicine should never be chewed or crushed. After taking a dose, avoid taking more than one pill in 24 hours. Don't follow the doctor's instructions. You've consumed alcohol, grapefruit, or any other recreational substance.