Drug interactions
Fentanyl + Metaxalone
Severity: Major
Fentanyl and Metaxalone: 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
Metaxalone is a sedating muscle relaxant, and giving it with fentanyl increases drowsiness, impaired psychomotor function and the risk of respiratory depression. Opioid labeling warns about concurrent use of opioids with other CNS depressants because of the risk of profound sedation, respiratory depression, coma and death.
What this interaction means in plain words
Fentanyl and Metaxalone 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 belongs to Musculoskeletal; Metaxalone belongs to Musculoskeletal.
Why it happens
Additive central nervous system depression through pharmacodynamic synergy.
What to do
Reserve the combination for patients in whom other options are inadequate, using the lowest effective doses and the shortest duration. Monitor for sedation and respiratory depression and counsel patients to avoid driving and alcohol.
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?
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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 Metaxalone
Frequently asked questions
Can I take Fentanyl with Metaxalone?
MediHelp rates the interaction as major. Fentanyl and Metaxalone 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. Metaxalone is a sedating muscle relaxant, and giving it with fentanyl increases drowsiness, impaired psychomotor function and the risk of respiratory depression. Opioid labeling warns about concurrent use of opioids with other CNS depressants because of the risk of profound sedation, respiratory depression, coma and death.
How serious is the interaction between Fentanyl and Metaxalone?
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 the combination for patients in whom other options are inadequate, using the lowest effective doses and the shortest duration. Monitor for sedation and respiratory depression and counsel patients to avoid driving and alcohol.
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.
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