Sildenafil (Viagra) is used to treat erectile dysfunction (impotence; the inability to get an erection or maintain an erection) in men. It is also used to improve exercise capacity in adults (Liqrev, Revatio) and children aged 1 year and over (Revatio) who have pulmonary arterial hypertension (PAH; high blood pressure in the blood vessels that carry blood to the lungs, resulting in shortness of breath, dizziness and tiredness).
Sildenafil belongs to the phosphodiesterase (PDE) inhibitor class of drugs. It treats erectile dysfunction by increasing blood flow to the penis during sexual stimulation. The increased blood flow can lead to an erection. In addition, it treats PAH by relaxing the blood vessels in the lungs so that blood can flow easily.
