Drug interactions
Esketamine + Ketamine
Severity: Major
Esketamine and Ketamine: major interaction.
Last updated Sources: UK 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 is the S-enantiomer of ketamine, so the two share the same NMDA antagonist pharmacology. Together they duplicate sedative, dissociative and pressor effects, with a risk of overdose-type toxicity.
What this interaction means in plain words
Esketamine and Ketamine 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; Ketamine belongs to Central Nervous System.
Why it happens
Therapeutic duplication of NMDA receptor antagonism.
What to do
Avoid concurrent use and do not give ketamine within a treatment course of esketamine unless supervised by specialists with full monitoring.
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 Ketamine, 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
- Esketamine 25 mg/ml solution for injection/infusion - SmPC sections 4.3/4.5 (names the partner; "e. Barbiturates and opiates given concurrently with esketamine may prolong the recovery phase. Diazepam is known to increase the half-life of racemic ketamine a") — electronic medicines compendium (UK SmPC)
Other interactions of Esketamine
Other interactions of Ketamine
Frequently asked questions
Can I take Esketamine with Ketamine?
MediHelp rates the interaction as major. Esketamine and Ketamine 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 is the S-enantiomer of ketamine, so the two share the same NMDA antagonist pharmacology. Together they duplicate sedative, dissociative and pressor effects, with a risk of overdose-type toxicity.
How serious is the interaction between Esketamine and Ketamine?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid concurrent use and do not give ketamine within a treatment course of esketamine unless supervised by specialists with full monitoring.
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.
