Drug interactions
Efavirenz + Mitotane
Severity: Major
Efavirenz and Mitotane: major 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
Mitotane is a strong CYP3A4 inducer and can substantially lower efavirenz concentrations, risking HIV treatment failure and resistance. The inducing effect can persist for weeks after mitotane is stopped.
What this interaction means in plain words
Efavirenz and Mitotane can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Efavirenz belongs to Anti Virals; Mitotane belongs to Oncology.
Why it happens
Mitotane induces CYP3A4 and CYP2B6, increasing efavirenz clearance.
What to do
Avoid if possible and use an antiretroviral regimen less affected by induction. If combined, monitor HIV viral load and efavirenz levels.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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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
Other interactions of Mitotane
- Doravirine + Mitotane Contraindicated
- Fostemsavir + Mitotane Contraindicated
- Lorlatinib + Mitotane Contraindicated
- Abiraterone + Mitotane Major
- Apixaban + Mitotane Major
- Aprepitant + Mitotane Major
Frequently asked questions
Can I take Efavirenz with Mitotane?
MediHelp rates the interaction as major. Efavirenz and Mitotane can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Mitotane is a strong CYP3A4 inducer and can substantially lower efavirenz concentrations, risking HIV treatment failure and resistance. The inducing effect can persist for weeks after mitotane is stopped.
How serious is the interaction between Efavirenz and Mitotane?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid if possible and use an antiretroviral regimen less affected by induction. If combined, monitor HIV viral load and efavirenz levels.
What other medicines interact with Efavirenz?
MediHelp also lists interactions of Efavirenz with, for example, Cobimetinib, Dienogest / estradiol valerate, Dihydroergotamine intranasal. The full list is on the Efavirenz page.
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