Drug interactions
Fentanyl transmucosal + Isoflurane
Severity: Major
Fentanyl transmucosal and Isoflurane: 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
Fentanyl and isoflurane both depress the central nervous system and respiration. Together they cause deeper sedation, hypotension and respiratory depression than either alone.
What this interaction means in plain words
Fentanyl transmucosal and Isoflurane 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 central nervous system and respiratory depression through opioid receptor agonism and enhancement of GABA-mediated inhibition by the volatile anesthetic.
What to do
Account for recent transmucosal fentanyl doses when planning anesthesia and reduce other opioid and anesthetic doses as needed. Monitor ventilation, oxygenation and blood pressure continuously, and have naloxone and airway equipment available.
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 Fentanyl transmucosal and Isoflurane, 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 14 days on the web. No card needed.
Other interactions of Isoflurane
Frequently asked questions
Can I take Fentanyl transmucosal with Isoflurane?
MediHelp rates the interaction as major. Fentanyl transmucosal and Isoflurane 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 and isoflurane both depress the central nervous system and respiration. Together they cause deeper sedation, hypotension and respiratory depression than either alone.
How serious is the interaction between Fentanyl transmucosal and Isoflurane?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Account for recent transmucosal fentanyl doses when planning anesthesia and reduce other opioid and anesthetic doses as needed. Monitor ventilation, oxygenation and blood pressure continuously, and have naloxone and airway equipment available.
What other medicines interact with Isoflurane?
MediHelp also lists interactions of Isoflurane with, for example, Adrenaline-articaine, Amisulpride, Arsenic trioxide. The full list is on the Isoflurane 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.
