Drug interactions
Efavirenz + Oxycodone
Severity: Moderate
Efavirenz and Oxycodone: 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
Efavirenz induces CYP3A4 and can lower oxycodone concentrations, potentially reducing analgesia. Withdrawal symptoms may occur in opioid-dependent patients, and stopping efavirenz can later lead to increased oxycodone exposure.
What this interaction means in plain words
Efavirenz and Oxycodone 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.
Efavirenz belongs to Anti Virals; Oxycodone belongs to Musculoskeletal.
Why it happens
Induction of CYP3A4-mediated oxycodone metabolism by efavirenz.
What to do
Monitor pain control and withdrawal signs and titrate oxycodone upward as needed. Reduce the dose and monitor for toxicity if efavirenz is discontinued.
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 Oxycodone
- Alvimopan + Oxycodone Contraindicated
- Calcium / magnesium / potassium / sodium oxybates + Oxycodone Contraindicated
- Isocarboxazid + Oxycodone Contraindicated
- Olanzapine / samidorphan + Oxycodone Contraindicated
- Oxycodone + Phenelzine Contraindicated
- Oxycodone + Sodium oxybate Contraindicated
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 Oxycodone?
MediHelp rates the interaction as moderate. Efavirenz and Oxycodone 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. Efavirenz induces CYP3A4 and can lower oxycodone concentrations, potentially reducing analgesia. Withdrawal symptoms may occur in opioid-dependent patients, and stopping efavirenz can later lead to increased oxycodone exposure.
How serious is the interaction between Efavirenz and Oxycodone?
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 pain control and withdrawal signs and titrate oxycodone upward as needed. Reduce the dose and monitor for toxicity if efavirenz is discontinued.
What other medicines interact with Oxycodone?
MediHelp also lists interactions of Oxycodone with, for example, Alvimopan, Calcium / magnesium / potassium / sodium oxybates, Isocarboxazid. The full list is on the Oxycodone page.
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