Drug interactions
Morphine + Orphenadrine
Severity: Moderate
Morphine and Orphenadrine: moderate 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
Orphenadrine is an anticholinergic muscle relaxant with sedative properties and may add to the CNS depression of morphine. Anticholinergic effects such as constipation and urinary retention may also be worsened.
What this interaction means in plain words
Morphine and Orphenadrine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
Additive CNS depression and additive anticholinergic effects on gut and bladder.
What to do
Use the lowest effective doses and monitor sedation, respiration, bowel and bladder function. Take particular care in older patients.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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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 Morphine with Orphenadrine?
MediHelp rates the interaction as moderate. Morphine and Orphenadrine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Orphenadrine is an anticholinergic muscle relaxant with sedative properties and may add to the CNS depression of morphine. Anticholinergic effects such as constipation and urinary retention may also be worsened.
How serious is the interaction between Morphine and Orphenadrine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Use the lowest effective doses and monitor sedation, respiration, bowel and bladder function. Take particular care in older patients.
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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