Drug interactions
Carbamazepine + Losartan
Severity: Moderate
Carbamazepine 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
Carbamazepine may reduce plasma concentrations of losartan and its active metabolite. This can weaken the antihypertensive effect.
What this interaction means in plain words
Carbamazepine 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.
Carbamazepine belongs to Central Nervous System; Losartan belongs to Cardiovascular.
Why it happens
Carbamazepine induces CYP3A4 and CYP2C9, which increases losartan metabolism.
What to do
Monitor blood pressure when starting or stopping carbamazepine. Adjust the losartan dose or switch to another agent if control is lost.
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 Carbamazepine
- Artemether / lumefantrine + Carbamazepine Contraindicated
- Cabotegravir + Carbamazepine Contraindicated
- Carbamazepine + Delamanid Contraindicated
- Carbamazepine + Dienogest / estradiol valerate Contraindicated
- Carbamazepine + Doravirine Contraindicated
- Carbamazepine + Elbasvir / grazoprevir Contraindicated
Frequently asked questions
Can I take Carbamazepine with Losartan?
MediHelp rates the interaction as moderate. Carbamazepine 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. Carbamazepine may reduce plasma concentrations of losartan and its active metabolite. This can weaken the antihypertensive effect.
How serious is the interaction between Carbamazepine 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 starting or stopping carbamazepine. Adjust the losartan dose or switch to another agent if control is lost.
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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