Drug interactions
Linezolid + Morphine
Severity: Major
Linezolid and Morphine: 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
Linezolid is a reversible, non-selective MAO inhibitor, and combining it with an opioid raises the risk of serotonin syndrome, with agitation, hyperthermia, clonus and autonomic instability. Morphine has weak serotonergic activity so the risk is lower than with meperidine or methadone, but additive CNS depression and blood pressure changes are also possible.
What this interaction means in plain words
Linezolid 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.
Linezolid belongs to Anti Bacterial; Morphine belongs to Musculoskeletal.
Why it happens
Linezolid inhibits MAO and may add to serotonergic effects of the opioid, with additive CNS depressant effects.
What to do
Prefer an alternative antibiotic or analgesic where possible; if both are essential, use the lowest effective morphine dose and monitor closely for serotonin toxicity, sedation and hypotension. Stop the combination promptly if neuromuscular, autonomic or mental status changes appear.
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 Morphine
- Alvimopan + Morphine Contraindicated
- Isocarboxazid + Morphine Contraindicated
- Morphine + Olanzapine / samidorphan Contraindicated
- Morphine + Phenelzine Contraindicated
- Morphine + Tranylcypromine Contraindicated
- Alfentanil + Morphine Major
Other interactions of Linezolid
- Amoxapine + Linezolid Contraindicated
- Atomoxetine + Linezolid Contraindicated
- Benzphetamine + Linezolid Contraindicated
- Brimonidine + Linezolid Contraindicated
- Bupropion-naltrexone + Linezolid Contraindicated
- Bupropion + Linezolid Contraindicated
Frequently asked questions
Can I take Linezolid with Morphine?
MediHelp rates the interaction as major. Linezolid 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. Linezolid is a reversible, non-selective MAO inhibitor, and combining it with an opioid raises the risk of serotonin syndrome, with agitation, hyperthermia, clonus and autonomic instability. Morphine has weak serotonergic activity so the risk is lower than with meperidine or methadone, but additive CNS depression and blood pressure changes are also possible.
How serious is the interaction between Linezolid 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: Prefer an alternative antibiotic or analgesic where possible; if both are essential, use the lowest effective morphine dose and monitor closely for serotonin toxicity, sedation and hypotension. Stop the combination promptly if neuromuscular, autonomic or mental status changes appear.
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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