Drug interactions
Levorphanol + Morphine
Severity: Major
Levorphanol 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
Combining two full opioid agonists increases the risk of excessive sedation, respiratory depression, and overdose. Therapeutic duplication is rarely justified outside carefully supervised opioid rotation.
What this interaction means in plain words
Levorphanol 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.
Why it happens
Additive mu-opioid receptor agonism causing CNS and respiratory depression.
What to do
Avoid concurrent use unless during planned rotation; then use reduced doses with close monitoring of sedation and respiratory rate.
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
Frequently asked questions
Can I take Levorphanol with Morphine?
MediHelp rates the interaction as major. Levorphanol 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. Combining two full opioid agonists increases the risk of excessive sedation, respiratory depression, and overdose. Therapeutic duplication is rarely justified outside carefully supervised opioid rotation.
How serious is the interaction between Levorphanol 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 concurrent use unless during planned rotation; then use reduced doses with close monitoring of sedation and respiratory rate.
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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