Drug interactions
Promethazine + Sevoflurane
Severity: Moderate
Promethazine 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
Promethazine adds to the CNS depressant effect of sevoflurane and may deepen anesthesia or prolong recovery. Both agents can also affect the QT interval.
What this interaction means in plain words
Promethazine 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.
Promethazine belongs to Respiratory; Sevoflurane belongs to Central Nervous System.
Why it happens
Additive CNS depression and possible additive QT prolongation.
What to do
Titrate the anesthetic to effect and monitor ECG, blood pressure and ventilation. Anticipate slower recovery.
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 Promethazine 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 Promethazine
- Ibutilide + Promethazine Contraindicated
- Pimozide + Promethazine Contraindicated
- Promethazine + Thioridazine Contraindicated
- Alfentanil + Promethazine Major
- Amiodarone + Promethazine Major
- Amisulpride + Promethazine Major
Other interactions of Sevoflurane
Frequently asked questions
Can I take Promethazine with Sevoflurane?
MediHelp rates the interaction as moderate. Promethazine 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. Promethazine adds to the CNS depressant effect of sevoflurane and may deepen anesthesia or prolong recovery. Both agents can also affect the QT interval.
How serious is the interaction between Promethazine 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: Titrate the anesthetic to effect and monitor ECG, blood pressure and ventilation. Anticipate slower recovery.
What other medicines interact with Promethazine?
MediHelp also lists interactions of Promethazine with, for example, Ibutilide, Pimozide, Thioridazine. The full list is on the Promethazine 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.
