Fildena 100 is a medication used to treat erectile dysfunction problems. This drug is also known as sildenafil. It works by helping to improve blood flow to the penis, which can help with erections. Side effects of this drug may include headache, flushing, and dizziness. Fildena is a pill that is meant to treat erectile dysfunction problems. It works by helping to increase blood flow to the penis. This can help to improve the ability to get and hold an erection.