Drug interactions
Efavirenz + Suvorexant
Severity: Moderate
Efavirenz and Suvorexant: 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 reduce suvorexant levels, which can lead to decreased effectiveness for insomnia. Suvorexant labeling advises that CYP3A4 inducers may reduce its efficacy.
What this interaction means in plain words
Efavirenz and Suvorexant 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; Suvorexant belongs to Central Nervous System.
Why it happens
Efavirenz induces CYP3A4, which is the main metabolic pathway of suvorexant.
What to do
Monitor sleep response and consider a dose increase within the labeled maximum if needed. Consider an alternative hypnotic if the response remains inadequate.
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 Suvorexant
Frequently asked questions
Can I take Efavirenz with Suvorexant?
MediHelp rates the interaction as moderate. Efavirenz and Suvorexant 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 reduce suvorexant levels, which can lead to decreased effectiveness for insomnia. Suvorexant labeling advises that CYP3A4 inducers may reduce its efficacy.
How serious is the interaction between Efavirenz and Suvorexant?
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 sleep response and consider a dose increase within the labeled maximum if needed. Consider an alternative hypnotic if the response remains inadequate.
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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