Drug interactions
Carbamazepine + Hydrochlorothiazide-losartan
Severity: Moderate
Carbamazepine and Hydrochlorothiazide-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 can induce losartan metabolism and weaken blood pressure control. Both carbamazepine and hydrochlorothiazide can also lower sodium, so combined use raises the risk of clinically significant hyponatremia.
What this interaction means in plain words
Carbamazepine and Hydrochlorothiazide-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; Hydrochlorothiazide-losartan belongs to Cardiovascular.
Why it happens
Carbamazepine induces CYP enzymes that metabolise losartan, and carbamazepine's ADH-like effect adds to thiazide-induced sodium loss.
What to do
Monitor serum sodium regularly, especially early in therapy and in older patients, and check blood pressure, raising the losartan dose 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 Hydrochlorothiazide-losartan
- Aliskiren + Hydrochlorothiazide-losartan Contraindicated
- Dofetilide + Hydrochlorothiazide-losartan Contraindicated
- Hydrochlorothiazide-losartan + Sparsentan Contraindicated
- Aceclofenac + Hydrochlorothiazide-losartan Major
- Aldesleukin + Hydrochlorothiazide-losartan Major
- Amifostine + Hydrochlorothiazide-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 Hydrochlorothiazide-losartan?
MediHelp rates the interaction as moderate. Carbamazepine and Hydrochlorothiazide-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 can induce losartan metabolism and weaken blood pressure control. Both carbamazepine and hydrochlorothiazide can also lower sodium, so combined use raises the risk of clinically significant hyponatremia.
How serious is the interaction between Carbamazepine and Hydrochlorothiazide-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 serum sodium regularly, especially early in therapy and in older patients, and check blood pressure, raising the losartan dose if control is lost.
What other medicines interact with Hydrochlorothiazide-losartan?
MediHelp also lists interactions of Hydrochlorothiazide-losartan with, for example, Aliskiren, Dofetilide, Sparsentan. The full list is on the Hydrochlorothiazide-losartan page.
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