Drug interactions
Cenobamate + Efavirenz
Severity: Moderate
Cenobamate and Efavirenz: 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
Cenobamate induces CYP3A4 and CYP2B6, the main enzymes clearing efavirenz, and may lower efavirenz concentrations enough to risk virologic failure. Both agents also cause somnolence and dizziness.
What this interaction means in plain words
Cenobamate and Efavirenz 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.
Cenobamate belongs to Central Nervous System; Efavirenz belongs to Anti Virals.
Why it happens
Cenobamate induces CYP2B6 and CYP3A4, increasing efavirenz metabolism; CNS effects are additive.
What to do
Monitor HIV viral load and consider efavirenz concentration measurement. Watch for additive sedation and dizziness.
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 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 Cenobamate
Frequently asked questions
Can I take Cenobamate with Efavirenz?
MediHelp rates the interaction as moderate. Cenobamate and Efavirenz 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. Cenobamate induces CYP3A4 and CYP2B6, the main enzymes clearing efavirenz, and may lower efavirenz concentrations enough to risk virologic failure. Both agents also cause somnolence and dizziness.
How serious is the interaction between Cenobamate and Efavirenz?
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 HIV viral load and consider efavirenz concentration measurement. Watch for additive sedation and dizziness.
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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