Drug interactions
Efavirenz + Sevoflurane
Severity: Moderate
Efavirenz and Sevoflurane: 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
Both can prolong the QT interval, so general anaesthesia with sevoflurane in a patient taking efavirenz may add to the risk of arrhythmia. The effect is mainly relevant in patients with other QT risk factors.
What this interaction means in plain words
Efavirenz and Sevoflurane 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; Sevoflurane belongs to Central Nervous System.
Why it happens
Additive effects on cardiac repolarization causing QT prolongation.
What to do
Review a recent ECG before surgery and correct potassium and magnesium. Maintain ECG monitoring during anaesthesia and avoid other QT-prolonging agents perioperatively.
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 Sevoflurane
Frequently asked questions
Can I take Efavirenz with Sevoflurane?
MediHelp rates the interaction as moderate. Efavirenz and Sevoflurane 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. Both can prolong the QT interval, so general anaesthesia with sevoflurane in a patient taking efavirenz may add to the risk of arrhythmia. The effect is mainly relevant in patients with other QT risk factors.
How serious is the interaction between Efavirenz and Sevoflurane?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Review a recent ECG before surgery and correct potassium and magnesium. Maintain ECG monitoring during anaesthesia and avoid other QT-prolonging agents perioperatively.
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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