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Drug interactions

Fentanyl + Flurazepam

Severity: Major

Fentanyl and Flurazepam: major 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

Combining an opioid with a benzodiazepine causes additive central nervous system and respiratory depression. It can lead to profound sedation, hypotension, coma and death.

What this interaction means in plain words

Fentanyl and Flurazepam 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.

Evidence level: High

Why it happens

Additive pharmacodynamic CNS depression via opioid receptors and GABA-A potentiation.

What to do

Reserve concurrent use for patients without adequate alternatives, using the lowest doses and shortest duration. Monitor respiratory rate and level of sedation.

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?

Bring a full list of your medicines, including over-the-counter products, supplements and herbal remedies, to every pharmacy visit.

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Frequently asked questions

Can I take Fentanyl with Flurazepam?

MediHelp rates the interaction as major. Fentanyl and Flurazepam 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. Combining an opioid with a benzodiazepine causes additive central nervous system and respiratory depression. It can lead to profound sedation, hypotension, coma and death.

How serious is the interaction between Fentanyl and Flurazepam?

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 concurrent use for patients without adequate alternatives, using the lowest doses and shortest duration. Monitor respiratory rate and level of sedation.

What other medicines interact with Fentanyl?

MediHelp also lists interactions of Fentanyl with, for example, Alvimopan, Isocarboxazid, Olanzapine / samidorphan. The full list is on the Fentanyl 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.

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