Fildena 100 mg pills are used for the treatment of erectile dysfunction and pulmonary arterial hypertension. Erectile Dysfunction – an inability to achieve or sustain an erection satisfactory enough for sexual intercourse.Pulmonary Arterial Hypertension – a condition that causes high blood pressure in the arteries that go from your heart to your lungs. This leads to the narrowing or blockage of tiny arteries in the lungs.