Drug interactions
Clobazam + Efavirenz
Severity: Moderate
Clobazam 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
Efavirenz may inhibit CYP2C19, raising levels of the active metabolite N-desmethylclobazam, while also inducing CYP3A4, which has a mixed effect on clobazam clearance. Additive sedation and CNS depression may occur.
What this interaction means in plain words
Clobazam 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.
Clobazam belongs to Central Nervous System; Efavirenz belongs to Anti Virals.
Why it happens
Efavirenz alters CYP2C19 and CYP3A4 metabolism of clobazam, and both drugs cause CNS depression.
What to do
Monitor for sedation and seizure control, and adjust clobazam dose as needed.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Clobazam and Efavirenz, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
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 Clobazam
- Amobarbital + Clobazam Major
- Buprenorphine + Clobazam Major
- Butorphanol + Clobazam Major
- Carisoprodol + Clobazam Major
- Chloral hydrate + Clobazam Major
- Clobazam + Clozapine Major
Frequently asked questions
Can I take Clobazam with Efavirenz?
MediHelp rates the interaction as moderate. Clobazam 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. Efavirenz may inhibit CYP2C19, raising levels of the active metabolite N-desmethylclobazam, while also inducing CYP3A4, which has a mixed effect on clobazam clearance. Additive sedation and CNS depression may occur.
How serious is the interaction between Clobazam 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 for sedation and seizure control, and adjust clobazam dose as needed.
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.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
