Drug interactions
Esketamine + Fentanyl
Severity: Major
Esketamine and Fentanyl: major interaction.
Last updated Sources: EMA SmPC
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
Esketamine and opioids such as fentanyl both cause sedation and can impair consciousness and respiratory drive. Together they may produce deeper sedation and respiratory depression than either alone.
What this interaction means in plain words
Esketamine and Fentanyl can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Esketamine belongs to Central Nervous System; Fentanyl belongs to Musculoskeletal.
Why it happens
Additive CNS and respiratory depression from NMDA antagonism and mu-opioid agonism.
What to do
Monitor sedation level and respiratory status, including pulse oximetry, during and after esketamine administration. Use the lowest effective opioid dose.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Esketamine and Fentanyl, 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.
References
Other interactions of Esketamine
Other interactions of Fentanyl
- Alvimopan + Fentanyl Contraindicated
- Fentanyl + Isocarboxazid Contraindicated
- Fentanyl + Olanzapine / samidorphan Contraindicated
- Fentanyl + Phenelzine Contraindicated
- Fentanyl + Tranylcypromine Contraindicated
- Alfentanil + Fentanyl Major
Frequently asked questions
Can I take Esketamine with Fentanyl?
MediHelp rates the interaction as major. Esketamine and Fentanyl can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Esketamine and opioids such as fentanyl both cause sedation and can impair consciousness and respiratory drive. Together they may produce deeper sedation and respiratory depression than either alone.
How serious is the interaction between Esketamine and Fentanyl?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor sedation level and respiratory status, including pulse oximetry, during and after esketamine administration. Use the lowest effective opioid dose.
What other medicines interact with Esketamine?
MediHelp also lists interactions of Esketamine with, for example, Alfentanil, Amobarbital, Belladonna and opium. The full list is on the Esketamine 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.
