Drug interactions
Efavirenz + Olaparib
Severity: Major
Efavirenz and Olaparib: 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
Efavirenz is a moderate CYP3A inducer and may reduce olaparib concentrations, potentially lessening antitumor efficacy.
What this interaction means in plain words
Efavirenz and Olaparib 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; Olaparib belongs to Oncology.
Why it happens
Induction of CYP3A4 by efavirenz increases the metabolic clearance of olaparib, a CYP3A substrate.
What to do
Avoid the combination where possible and choose an alternative antiretroviral. If it cannot be avoided, monitor for reduced oncologic response.
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 Olaparib
- Amiodarone + Olaparib Major
- Amobarbital + Olaparib Major
- Apalutamide + Olaparib Major
- Aprepitant + Olaparib Major
- Azathioprine + Olaparib Major
- Carbamazepine + Olaparib Major
Frequently asked questions
Can I take Efavirenz with Olaparib?
MediHelp rates the interaction as major. Efavirenz and Olaparib 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 is a moderate CYP3A inducer and may reduce olaparib concentrations, potentially lessening antitumor efficacy.
How serious is the interaction between Efavirenz and Olaparib?
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 the combination where possible and choose an alternative antiretroviral. If it cannot be avoided, monitor for reduced oncologic response.
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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