Bosentan Key Prescribing Points: Indication, Dosage, Risks, and Monitoring

　　Indication and mechanism

　　Bosentan is a dual endothelin receptor antagonist.It competitively blocks ETA and ETB receptors,reducing endothelin-1 mediated vasoconstriction and vascular remodeling,thereby lowering pulmonary vascular resistance.

　　Its main labeled use is WHO functional class II–IV pulmonary arterial hypertension,including idiopathic or heritable PAH,connective tissue disease–associated PAH,and congenital heart disease–associated PAH.The goal is to improve exercise capacity and reduce clinical deterioration.

　　Dosage and administration

　　For adults,a common regimen is 62.5 mg twice daily for the first 4 weeks,then 125 mg twice daily.Doses above this level do not add clear benefit and increase liver injury risk.

　　Pediatric use depends on age,body weight,formulation,and local labeling,and should not simply copy the adult schedule.Doses should be taken regularly;a missed dose should not be doubled,and stopping or tapering should be physician-directed.

　　Adverse effects and contraindications

　　Common issues include headache,peripheral edema,anemia,and abnormal liver tests.

　　Key safety limits:

　　Pregnancy is contraindicated because of teratogenic risk

　　Moderate-to-severe liver impairment or markedly elevated transaminases limits use

　　Concomitant cyclosporine A or glibenclamide is contraindicated

　　Liver transaminases are usually checked before treatment and monthly during treatment

　　Drug interactions should be reviewed before adding or stopping other medicines.

　　Storage

　　Bosentan tablets are usually stored at room temperature,according to the product package leaflet.Keep away from children,and avoid moisture or damaged packaging.