Drug interactions
Clozapine + Sevoflurane
Severity: Moderate
Clozapine 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 clozapine and sevoflurane can prolong the QT interval, so perioperative use may add to the risk of ventricular arrhythmias including torsades de pointes. Clozapine also contributes hypotension and sedation under anaesthesia.
What this interaction means in plain words
Clozapine 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.
Clozapine belongs to Central Nervous System; Sevoflurane belongs to Central Nervous System.
Why it happens
Additive QT prolongation through cardiac repolarisation effects (hERG potassium channel inhibition) of both agents.
What to do
Obtain a baseline ECG and correct potassium and magnesium before anaesthesia, and monitor ECG continuously during and after surgery. Avoid other QT-prolonging drugs such as ondansetron where possible in the perioperative period.
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 Clozapine and Sevoflurane, 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 Clozapine
- Clozapine + Deferiprone Contraindicated
- Clozapine + Irinotecan Contraindicated
- Clozapine + Pimozide Contraindicated
- Clozapine + Thioridazine Contraindicated
- Acalabrutinib + Clozapine Major
- Adagrasib + Clozapine Major
Other interactions of Sevoflurane
Frequently asked questions
Can I take Clozapine with Sevoflurane?
MediHelp rates the interaction as moderate. Clozapine 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 clozapine and sevoflurane can prolong the QT interval, so perioperative use may add to the risk of ventricular arrhythmias including torsades de pointes. Clozapine also contributes hypotension and sedation under anaesthesia.
How serious is the interaction between Clozapine 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: Obtain a baseline ECG and correct potassium and magnesium before anaesthesia, and monitor ECG continuously during and after surgery. Avoid other QT-prolonging drugs such as ondansetron where possible in the perioperative period.
What other medicines interact with Clozapine?
MediHelp also lists interactions of Clozapine with, for example, Deferiprone, Irinotecan, Pimozide. The full list is on the Clozapine 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.
