Drug interactions
Clonazepam + Fentanyl intranasal
Severity: Major
Clonazepam and Fentanyl intranasal: major interaction.
Last updated Sources: US FDA label
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
Fentanyl combined with a benzodiazepine causes additive sedation and respiratory depression that can be fatal. Intranasal fentanyl is potent, which heightens the risk.
What this interaction means in plain words
Clonazepam and Fentanyl intranasal 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.
Why it happens
Additive CNS and respiratory depression from opioid receptor agonism and GABA-A potentiation.
What to do
Reserve combined use for patients lacking alternatives, with the lowest doses and shortest duration. Monitor closely for sedation and respiratory depression.
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 Clonazepam and Fentanyl intranasal, 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 Clonazepam
- Calcium / magnesium / potassium / sodium oxybates + Clonazepam Contraindicated
- Clonazepam + Sodium oxybate Contraindicated
- Alfentanil + Clonazepam Major
- Alprazolam + Clonazepam Major
- Amobarbital + Clonazepam Major
- Belladonna and opium + Clonazepam Major
Frequently asked questions
Can I take Clonazepam with Fentanyl intranasal?
MediHelp rates the interaction as major. Clonazepam and Fentanyl intranasal 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. Fentanyl combined with a benzodiazepine causes additive sedation and respiratory depression that can be fatal. Intranasal fentanyl is potent, which heightens the risk.
How serious is the interaction between Clonazepam and Fentanyl intranasal?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Reserve combined use for patients lacking alternatives, with the lowest doses and shortest duration. Monitor closely for sedation and respiratory depression.
What other medicines interact with Clonazepam?
MediHelp also lists interactions of Clonazepam with, for example, Calcium / magnesium / potassium / sodium oxybates, Sodium oxybate, Alfentanil. The full list is on the Clonazepam 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.
