Drug interactions
Efavirenz + Hydrochlorothiazide-losartan
Severity: Minor
Efavirenz and Hydrochlorothiazide-losartan: minor 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
Efavirenz is a mixed CYP inducer and may also affect CYP2C9, so exposure to losartan and its active metabolite E-3174 may change unpredictably. The clinical effect on blood pressure control is not well established.
What this interaction means in plain words
Efavirenz and Hydrochlorothiazide-losartan have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Efavirenz belongs to Anti Virals; Hydrochlorothiazide-losartan belongs to Cardiovascular.
Why it happens
Efavirenz modulates CYP2C9 and CYP3A4 activity, which may alter conversion of losartan to its active metabolite; the net effect is uncertain.
What to do
Monitor blood pressure after starting or stopping efavirenz. Adjust the losartan dose according to the antihypertensive response.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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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 Efavirenz
- Cobimetinib + Efavirenz Contraindicated
- Dienogest / estradiol valerate + Efavirenz Contraindicated
- Dihydroergotamine intranasal + Efavirenz Contraindicated
- Dihydroergotamine + Efavirenz Contraindicated
- Doravirine + Efavirenz Contraindicated
- Efavirenz + Elbasvir / grazoprevir Contraindicated
Frequently asked questions
Can I take Efavirenz with Hydrochlorothiazide-losartan?
MediHelp rates the interaction as minor. Efavirenz and Hydrochlorothiazide-losartan have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Efavirenz is a mixed CYP inducer and may also affect CYP2C9, so exposure to losartan and its active metabolite E-3174 may change unpredictably. The clinical effect on blood pressure control is not well established.
How serious is the interaction between Efavirenz and Hydrochlorothiazide-losartan?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor blood pressure after starting or stopping efavirenz. Adjust the losartan dose according to the antihypertensive response.
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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