Treating high blood pressure in the lungs (pulmonary arterial hypertension [PAH]). It may also be used for other conditions as determined by your doctor.
Sildenafil is a phosphodiesterase type 5 (PDE5) inhibitor. It works by relaxing and dilating the blood vessels in the lungs. This lowers the blood pressure in the lungs and helps to improve your ability to exercise.
you are allergic to any ingredient in sildenafil
you have pulmonary veno-occlusive disease (PVOD)
you are taking nitrates (eg, isosorbide, nitroglycerin) in any form (eg, tablet, capsule, spray, patch, ointment) or nitroprusside
you take another medicine that contains sildenafil, another PDE5 inhibitor (eg, tadalafil, vardenafil), or ritonavir
you use certain recreational drugs called "poppers" (eg, amyl nitrate or nitrite, butyl nitrate or nitrite)
Contact your doctor or health care provider right away if any of these apply to you.
Indications and Usage for Sildenafil Injection