An update on sildenafil in the treatment of pulmonary arterial hypertension in the neonate

Abstract

Pulmonary arterial hypertension (PAH) refers to a group of diseases that are characterised by high pressure in the pulmonary artery and by pulmonary vascular resistance. Persistent PAH in the newborn is a condition whereby the pulmonary artery pressure does not decrease after birth, and may occur in as many as 6.8 in 1 000 live births. Phosphodiesterase type 5 (PDE-5) is the predominant PDE isoform in the lung which metabolises cyclic guanosine monophosphate (cGMP), and is upregulated in conditions associated with PAH. Thus, by selectively inhibiting PDE-5, the accumulation of intracellular cGMP is promoted by sildenafil citrate and nitric oxide-mediated vasodilatation is also enhanced. The article provides information on associated dosing regimens and reconstitution guidelines.