Drug interactions
Bosentan + Losartan
Severity: Moderate
Bosentan and Losartan: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Bosentan induces CYP2C9 and CYP3A4, which may lower exposure to losartan and its active metabolite. Both drugs lower blood pressure, so the net effect on control is variable.
What this interaction means in plain words
Bosentan and Losartan can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Bosentan belongs to Miscellaneous; Losartan belongs to Cardiovascular.
Why it happens
Induction of CYP2C9 and CYP3A4 by bosentan increases losartan metabolism, with additive hypotensive pharmacodynamics.
What to do
Monitor blood pressure when bosentan is started or stopped and adjust the losartan dose as needed.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Losartan
- Aliskiren + Losartan Contraindicated
- Losartan + Sparsentan Contraindicated
- Amifostine + Losartan Major
- Amiloride + Losartan Major
- Amlodipine-benazepril + Losartan Major
- Amlodipine-hydrochlorothiazide-valsartan + Losartan Major
Other interactions of Bosentan
- Bosentan + Cyclosporin Contraindicated
- Bosentan + Glibenclamide Contraindicated
- Bosentan + Glyburide-metformin Contraindicated
- Bosentan + Lonafarnib Contraindicated
- Bosentan + Sparsentan Contraindicated
- Artemether / lumefantrine + Bosentan Major
Frequently asked questions
Can I take Bosentan with Losartan?
MediHelp rates the interaction as moderate. Bosentan and Losartan can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Bosentan induces CYP2C9 and CYP3A4, which may lower exposure to losartan and its active metabolite. Both drugs lower blood pressure, so the net effect on control is variable.
How serious is the interaction between Bosentan and Losartan?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor blood pressure when bosentan is started or stopped and adjust the losartan dose as needed.
What other medicines interact with Losartan?
MediHelp also lists interactions of Losartan with, for example, Aliskiren, Sparsentan, Amifostine. The full list is on the Losartan page.
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