Sildigra 250mg is a brand name for a medication that contains Sildenafil Citrate, which is most commonly known as the active ingredient in Viagra. Sildenafil is used to treat erectile dysfunction (ED) and sometimes pulmonary arterial hypertension (PAH), a condition characterized by high blood pressure in the arteries of the lungs. Sildenafil is also prescribed in lower doses to treat PAH, where it helps relax the blood vessels in the lungs and reduces the workload on the heart.