Drug interactions
Lorazepam + Morphine
Severity: Major
Lorazepam 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
Concurrent opioids and benzodiazepines can cause profound sedation, respiratory depression, coma and death, a risk highlighted in regulatory boxed warnings. The risk rises with higher doses, longer use and in patients with respiratory disease or older age.
What this interaction means in plain words
Lorazepam 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.
Lorazepam belongs to Central Nervous System; Morphine belongs to Musculoskeletal.
Why it happens
Additive CNS and respiratory depression via mu-opioid receptor agonism and GABA-A potentiation.
What to do
Avoid the combination where possible; if necessary, use the lowest doses for the shortest duration and monitor for respiratory depression and sedation. Counsel patients and caregivers about warning signs.
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 Lorazepam
Frequently asked questions
Can I take Lorazepam with Morphine?
MediHelp rates the interaction as major. Lorazepam 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. Concurrent opioids and benzodiazepines can cause profound sedation, respiratory depression, coma and death, a risk highlighted in regulatory boxed warnings. The risk rises with higher doses, longer use and in patients with respiratory disease or older age.
How serious is the interaction between Lorazepam 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: Avoid the combination where possible; if necessary, use the lowest doses for the shortest duration and monitor for respiratory depression and sedation. Counsel patients and caregivers about warning signs.
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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