Bosentan is a drug that is prescribed to patients who suffer from pulmonary arterial hypertension, or PAH. PAH patients have difficulty breathing because of high blood pressure in the lungs. This medication widens the blood vessels in the lungs so that patients can breathe more easily and can exert themselves physically without losing their breath.
Pregnant women should not take this medication; it causes severe birth defects. In addition, this medication can interfere with the effectiveness of hormonal birth control methods, so women who are on this medication should use alternate forms of contraception.
Bosentan also can cause liver disease. Patients should contact their doctors immediately if they have stomach pain and nausea, especially if it is in combination with jaundice and extreme fatigue.