What it's for (Indications)
- Treatment of increased blood pressure in the lungs, also known as Pulmonary Arterial Hypertension (PAH), and for Systemic Sclerosis (hardening and thickening of skin surrounding organs and blood vessels).
Dosage Information
| Type | Guideline |
|---|---|
| Standard | For patients older than 12 years of age: initiate at 62.5 mg orally twice daily. For patients weighing greater than 40 kg, increase the dose to 125 mg orally twice daily after 4 weeks. For patients 12 years of age and younger: dosage is based on weight. Healthcare professionals who prescribe bosentan must enroll in the Bosentan REMS Program and comply with required monitoring. A pregnancy test must be obtained in females of reproductive potential prior to bosentan treatment, monthly during treatment, and one month after stopping bosentan. Treatment should only be initiated after a negative pregnancy test. The dose should be reduced for patients developing aminotransferase elevations more than 3 times the Upper Limit of Normal (ULN). |
Safety & Warnings
Common Side Effects
- Common adverse reactions include upper respiratory tract infections, pyrexia (fever), drowsiness, upset stomach, difficulty urinating, confusion, slight skin irritation, and headache.
Serious Warnings
- Black Box Warning: WARNING: RISKS OF HEPATOTOXICITY and EMBRYO-FETALTOXICITY Because of the risks of hepatotoxicity and birth defects, bosentan tablets for oral suspension is available only through a restricted program called the Bosentan REMS Program. Under the Bosentan REMS, prescribers, patients, and pharmacies must enroll in the program. Hepatotoxicity: In clinical studies, bosentan caused at least 3-fold upper limit of normal (ULN) elevation of liver aminotransferases (ALT or AST).
- Patients must be closely monitored for hepatotoxicity (liver injury), which can manifest as elevated liver aminotransferases (ALTs, ASTs) and bilirubin.
- Dose reduction is required if aminotransferase elevations exceed 3 times the Upper Limit of Normal (ULN).
- There is a significant risk of embryo-fetal toxicity, necessitating stringent pregnancy prevention measures and monitoring.
- Fluid retention, visible water retention, and acute decompensated heart failure (with sudden and serious symptoms or fluid in the lungs) require careful observation.
- Anemia and decreased blood platelets are potential risks.
- Patients with pre-existing breathing problems, liver, or kidney problems must observe caution.
- Elderly patients should also be monitored carefully.
- Due to potential drowsiness, patients should avoid tasks requiring alertness immediately after taking this medicine.
- Females of childbearing potential require regular pregnancy checks and must use two reliable forms of contraception during treatment and for one month after stopping bosentan.
- Hypersensitivity reactions may occur.
- The drug is available only through a restricted program (Bosentan REMS Program) due to its risks, requiring prescribers, patients, and pharmacies to enroll and comply with monitoring requirements.
How it Works (Mechanism of Action)
Bosentan is a specific and competitive antagonist at endothelin receptor types ETA and ETB. It has a slightly higher affinity for ETA receptors. Endothelin-1 (ET-1), a neurohormone elevated in PAH patients, mediates its effects by binding to ETA and ETB receptors in the endothelium and vascular smooth muscle.
Commercial Brands (Alternatives)
No other brands found for this formula.