From the Guidelines
Bosentan can cause fluid retention as a side effect, and patients should be monitored for signs of edema, such as sudden weight gain, increased swelling in extremities, or worsening shortness of breath. This medication, used primarily to treat pulmonary arterial hypertension, works by blocking endothelin receptors but may lead to edema in patients. According to the study 1, fluid retention and lower limb oedema have been reported in patients treated with Bosentan. The mechanism behind this side effect relates to bosentan's vasodilatory properties and its effects on kidney function through endothelin pathway modulation.
Key Points to Consider
- Patients taking bosentan should monitor for sudden weight gain (2+ pounds in 24 hours or 5+ pounds in a week), increased swelling in extremities, or worsening shortness of breath, as these may indicate fluid retention 1.
- Management typically involves dose adjustment, adding a diuretic like furosemide 20-40mg daily, or in severe cases, temporarily discontinuing the medication.
- Patients should maintain regular follow-up appointments for weight checks and physical examinations while on bosentan therapy.
- Those with pre-existing heart failure or kidney disease should be monitored more closely as they face higher risk of developing significant fluid retention.
Important Considerations
- Bosentan has been approved for the treatment of NYHA class III and IV PAH patients in the USA and Canada, and in Europe it has been approved by the EMEA for the treatment of NYHA class III patients specifying that efficacy has been demonstrated only in IPAH patients and PAH associated with scleroderma without significant lung fibrosis 1.
- Due to the potential increase in liver enzymes, the FDA requires that liver function tests be performed at least monthly in patients receiving bosentan, and the EMEA recommended to monitor monthly liver function tests 1.
From the Research
Relationship Between Bosentan and Fluid Retention
- Bosentan, also known as Tracleer, is an endothelin receptor antagonist used to treat pulmonary arterial hypertension 2.
- Endothelin receptor antagonists, including bosentan, have been associated with fluid retention, which can be a limiting factor in their use, particularly in patients with chronic kidney disease (CKD) 3, 4.
- The risk of fluid retention with endothelin receptor antagonists can be mitigated by combining them with other medications, such as sodium-glucose cotransporter 2 inhibitors, which have diuretic effects 3.
- In patients with end-stage renal disease, bosentan has been shown to be safe and effective, with no need for dose adjustment 2.
- Fluid retention is a major determinant of symptoms in patients with heart failure, and endothelin receptor antagonists may exacerbate this condition 5, 4.
- Close monitoring of body weight and other clinical indicators of fluid retention is recommended when using endothelin receptor antagonists, including bosentan, to minimize the risk of congestive heart failure 4.
- Other endothelin receptor antagonists, such as aprocitentan, have also been associated with fluid retention and edema as common adverse events 6.