A patient presents with hypertension and is tested for drugs affecting endothelin. Which condition is bosentan used for?

Bosentan is an endothelin receptor antagonist specifically used in the treatment of pulmonary arterial hypertension (PAH), which is classified as primary pulmonary hypertension when it occurs without an identified cause. Bosentan works by blocking the action of endothelin-1, a potent vasoconstrictor that plays a significant role in the pathophysiology of pulmonary hypertension. By antagonizing endothelin receptors, bosentan helps to reduce pulmonary vascular resistance and improve symptoms and exercise capacity in individuals with PAH.

This medication has shown to have beneficial effects in patients suffering from this condition, ultimately helping to enhance quality of life and exercise tolerance. It is important to note that while bosentan has precise indications, it is not indicated for other conditions like chronic migraine, heart failure, or systemic hypertension, making its use specifically valuable in the context of pulmonary arterial hypertension.