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Updated: May 31, 2026

Increasing Pulmonary Artery Pulsatile Flow Improves Hypoxic Pulmonary Hypertension in Piglets
Published on: May 11, 2015
Tadalafil for the treatment of pulmonary arterial hypertension
1Division of Pulmonary, Sleep and Critical Care Medicine, Rhode Island Hospital, Alpert Medical School, Brown University, 593 Eddy Street, Providence, RI 02903, USA. james_klinger@brown.edu.
Abstract:
Tadalafil is a selective inhibitor of phosphodiesterase type-5 (PDE-5) that was originally developed for the treatment of male erectile dysfunction and recently approved for the treatment of pulmonary arterial hypertension (PAH). The antipulmonary hypertensive effects of nitric oxide and the natriuretic peptides are mediated via increasing intracellular cGMP and enzymatic degradation by PDE-5 is the major route of cGMP inactivation in the lung. Evidence is accruing that PDE-5 activity is increased in pulmonary vascular diseases and may contribute to the pathogenesis of PAH. The longer half-life of tadalafil allows for once-daily dosing as compared with three-times daily dosing for sildenafil, the only other PDE-5 inhibitor currently approved for treatment of PAH. This article reviews the role of cGMP and PDE-5 in PAH, presents the results of recent clinical trials and discusses the role of tadalafil in the treatment of this rare but difficult-to-treat disease.
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