Drug interactions
Efavirenz + Modafinil
Severity: Minor
Efavirenz and Modafinil: minor 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 can induce CYP3A4, which contributes to modafinil clearance, so modafinil exposure may fall. The result may be reduced wakefulness-promoting effect.
What this interaction means in plain words
Efavirenz and Modafinil have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Efavirenz belongs to Anti Virals; Modafinil belongs to Central Nervous System.
Why it happens
Efavirenz induces CYP3A4-mediated metabolism of modafinil.
What to do
Assess clinical response to modafinil and increase the dose if needed within the labeled range.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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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 Modafinil
Frequently asked questions
Can I take Efavirenz with Modafinil?
MediHelp rates the interaction as minor. Efavirenz and Modafinil have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Efavirenz can induce CYP3A4, which contributes to modafinil clearance, so modafinil exposure may fall. The result may be reduced wakefulness-promoting effect.
How serious is the interaction between Efavirenz and Modafinil?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Assess clinical response to modafinil and increase the dose if needed within the labeled range.
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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