Drug interactions
Fentanyl + Methohexital
Severity: Major
Fentanyl and Methohexital: 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
Methohexital is a barbiturate anesthetic that adds to opioid sedation and respiratory depression. Hypotension, apnea and death can result without airway support.
What this interaction means in plain words
Fentanyl and Methohexital 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; Methohexital belongs to Central Nervous System.
Why it happens
Additive CNS depression through GABA-A potentiation and opioid receptor agonism.
What to do
Use only in monitored settings with airway equipment and ventilation capability, and reduce doses of each drug. Titrate carefully and monitor oxygenation and blood pressure.
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 Methohexital
Frequently asked questions
Can I take Fentanyl with Methohexital?
MediHelp rates the interaction as major. Fentanyl and Methohexital 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. Methohexital is a barbiturate anesthetic that adds to opioid sedation and respiratory depression. Hypotension, apnea and death can result without airway support.
How serious is the interaction between Fentanyl and Methohexital?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Use only in monitored settings with airway equipment and ventilation capability, and reduce doses of each drug. Titrate carefully and monitor oxygenation and blood pressure.
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.
