Drug interactions
Methadone + Oxazepam
Severity: Major
Methadone and Oxazepam: 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
Opioids combined with benzodiazepines can cause profound sedation, respiratory depression, coma and death. Oxazepam has no active metabolites and is less dependent on oxidative metabolism, but the pharmacodynamic risk remains.
What this interaction means in plain words
Methadone and Oxazepam 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.
Methadone belongs to Musculoskeletal; Oxazepam belongs to Central Nervous System.
Why it happens
Additive CNS and respiratory depression through opioid and GABA-A receptor effects.
What to do
Avoid the combination where possible; if needed, use the lowest effective doses for the shortest time. Monitor for sedation and respiratory depression and counsel patients and caregivers, considering naloxone availability.
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 Methadone
- Alvimopan + Methadone Contraindicated
- Calcium / magnesium / potassium / sodium oxybates + Methadone Contraindicated
- Droperidol + Methadone Contraindicated
- Ibutilide + Methadone Contraindicated
- Isocarboxazid + Methadone Contraindicated
- Lefamulin + Methadone Contraindicated
Other interactions of Oxazepam
- Calcium / magnesium / potassium / sodium oxybates + Oxazepam Contraindicated
- Oxazepam + Sodium oxybate Contraindicated
- Alfentanil + Oxazepam Major
- Amobarbital + Oxazepam Major
- Baclofen + Oxazepam Major
- Belladonna and opium + Oxazepam Major
Frequently asked questions
Can I take Methadone with Oxazepam?
MediHelp rates the interaction as major. Methadone and Oxazepam 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. Opioids combined with benzodiazepines can cause profound sedation, respiratory depression, coma and death. Oxazepam has no active metabolites and is less dependent on oxidative metabolism, but the pharmacodynamic risk remains.
How serious is the interaction between Methadone and Oxazepam?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination where possible; if needed, use the lowest effective doses for the shortest time. Monitor for sedation and respiratory depression and counsel patients and caregivers, considering naloxone availability.
What other medicines interact with Methadone?
MediHelp also lists interactions of Methadone with, for example, Alvimopan, Calcium / magnesium / potassium / sodium oxybates, Droperidol. The full list is on the Methadone page.
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