Drug interactions
Chloramphenicol + Fentanyl
Severity: Major
Chloramphenicol and Fentanyl: 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
Chloramphenicol inhibits CYP3A4 and may raise fentanyl exposure, increasing the risk of deep sedation and respiratory depression. The risk is greatest with sustained exposure or transmucosal/high-dose fentanyl.
What this interaction means in plain words
Chloramphenicol 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.
Chloramphenicol belongs to Anti Bacterial; Fentanyl belongs to Musculoskeletal.
Why it happens
Inhibition of CYP3A4-mediated fentanyl metabolism, raising plasma fentanyl concentrations.
What to do
Monitor frequently for respiratory depression and sedation and reduce the fentanyl dose as needed. Consider an alternative antibiotic or a less CYP3A4-dependent opioid.
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 Chloramphenicol 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.
Other interactions of Fentanyl
- Alvimopan + Fentanyl Contraindicated
- Fentanyl + Isocarboxazid Contraindicated
- Fentanyl + Olanzapine / samidorphan Contraindicated
- Fentanyl + Phenelzine Contraindicated
- Fentanyl + Tranylcypromine Contraindicated
- Alfentanil + Fentanyl Major
Other interactions of Chloramphenicol
Frequently asked questions
Can I take Chloramphenicol with Fentanyl?
MediHelp rates the interaction as major. Chloramphenicol 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. Chloramphenicol inhibits CYP3A4 and may raise fentanyl exposure, increasing the risk of deep sedation and respiratory depression. The risk is greatest with sustained exposure or transmucosal/high-dose fentanyl.
How serious is the interaction between Chloramphenicol 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 frequently for respiratory depression and sedation and reduce the fentanyl dose as needed. Consider an alternative antibiotic or a less CYP3A4-dependent opioid.
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.
