Safety and long-term efficacy of transition from sildenafil to tadalafil due to side effects in patients with pulmonary arterial hypertension.

Introduction Two phosphodiesterase-type 5 (PDE-5) inhibitors, sildenafiland tadalafil, are approved for treatment of pulmonary arterial hypertension (PAH). It has not yet been observed if transition from sildenafilto tadalafilis beneficial in patients suffering from adverse reactions. Aim of this study was to analyze safety and long-term effects in PAH patients whose treatment was transitioned from sildenafilto tadalafildue to intolerable side-effects.