Nitric oxide (NO) is a gas that has potent vasodilator properties. It can be administered via inhalation in situations where NO production is impaired and results in vasodilatation of the pulmonary capillaries. In term infants, the administration of inhaled NO, at a dose of 20 parts per million, may reduce the need for extracorporeal membrane oxygenation by reducing pulmonary vascular resistance and improving oxygenation. Inhaled NO is an approved therapy in term babies with severe hypoxemic respiratory failure. In premature infants, inhaled NO may increase bleeding time and decrease platelet aggregation resulting in an increased risk for intraventricular hemorrhage. Early administration of inhaled NO may also potentially decrease the risk for developing chronic lung disease in premature infants. However, since studies show conflicting results, inhaled NO should only be used in premature neonates following investigational review board approved protocols.