Fildena can be used to treat the symptoms of pulmonary arterial hypertension in both men and women. The area that joins the heart and lungs is where this type of hypertension occurs. When hypertension occurs in the lungs, the heart must work harder to pump enough blood through the lungs. Sildenafil works on the lungs' PDE5 enzyme to relax blood vessels. Consequently, the heart will have to exert less effort and pump more blood to the lungs. Certain medications should not be taken at specific times of the day or immediately before or after eating specific foods due to the possibility of interactions. It's important to be aware of these potential Fildena side effects and to seek medical attention if they worsen or continue.