Drug interactions
Chlorzoxazone + Morphine
Severity: Moderate
Chlorzoxazone and Morphine: 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
Chlorzoxazone is a centrally acting muscle relaxant that can add to morphine-induced drowsiness and impaired alertness. Respiratory depression is possible at higher doses.
What this interaction means in plain words
Chlorzoxazone and Morphine 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.
Chlorzoxazone belongs to Musculoskeletal; Morphine belongs to Musculoskeletal.
Why it happens
Additive central nervous system depression.
What to do
Use the lowest effective doses and monitor for sedation and respiratory depression. Advise patients against driving until the response is known.
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
Other interactions of Chlorzoxazone
Frequently asked questions
Can I take Chlorzoxazone with Morphine?
MediHelp rates the interaction as moderate. Chlorzoxazone and Morphine 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. Chlorzoxazone is a centrally acting muscle relaxant that can add to morphine-induced drowsiness and impaired alertness. Respiratory depression is possible at higher doses.
How serious is the interaction between Chlorzoxazone and Morphine?
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 for sedation and respiratory depression. Advise patients against driving until the response is known.
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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