Drug interactions
Methohexital + Morphine
Severity: Major
Methohexital and Morphine: major interaction.
Last updated Sources: US FDA label
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 and with morphine causes additive sedation, hypotension and respiratory depression. Opioids may reduce the barbiturate dose required for anesthesia.
What this interaction means in plain words
Methohexital and Morphine 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 belongs to Central Nervous System; Morphine belongs to Musculoskeletal.
Why it happens
Additive CNS depression through opioid receptor activation and GABA-A potentiation.
What to do
Use only in monitored settings with airway support and reduce methohexital doses as needed. Monitor blood pressure, oxygenation and ventilation.
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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References
Other interactions of Morphine
- Alvimopan + Morphine Contraindicated
- Isocarboxazid + Morphine Contraindicated
- Morphine + Olanzapine / samidorphan Contraindicated
- Morphine + Phenelzine Contraindicated
- Morphine + Tranylcypromine Contraindicated
- Alfentanil + Morphine Major
Other interactions of Methohexital
Frequently asked questions
Can I take Methohexital with Morphine?
MediHelp rates the interaction as major. Methohexital and Morphine 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 and with morphine causes additive sedation, hypotension and respiratory depression. Opioids may reduce the barbiturate dose required for anesthesia.
How serious is the interaction between Methohexital and Morphine?
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 support and reduce methohexital doses as needed. Monitor blood pressure, oxygenation and ventilation.
What other medicines interact with Morphine?
MediHelp also lists interactions of Morphine with, for example, Alvimopan, Isocarboxazid, Olanzapine / samidorphan. The full list is on the Morphine page.
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