Drug interactions
Metaxalone + Promethazine
Severity: Moderate
Metaxalone and Promethazine: 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
Both agents cause drowsiness and dizziness, so together they increase sedation and psychomotor impairment, with a higher risk of falls in older patients.
What this interaction means in plain words
Metaxalone and Promethazine 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.
Metaxalone belongs to Musculoskeletal; Promethazine belongs to Respiratory.
Why it happens
Additive CNS depression.
What to do
Use the lowest effective doses and warn patients against driving or operating machinery. Monitor older adults for excess sedation and falls.
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 Promethazine
- Ibutilide + Promethazine Contraindicated
- Pimozide + Promethazine Contraindicated
- Promethazine + Thioridazine Contraindicated
- Alfentanil + Promethazine Major
- Amiodarone + Promethazine Major
- Amisulpride + Promethazine Major
Other interactions of Metaxalone
Frequently asked questions
Can I take Metaxalone with Promethazine?
MediHelp rates the interaction as moderate. Metaxalone and Promethazine 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. Both agents cause drowsiness and dizziness, so together they increase sedation and psychomotor impairment, with a higher risk of falls in older patients.
How serious is the interaction between Metaxalone and Promethazine?
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 warn patients against driving or operating machinery. Monitor older adults for excess sedation and falls.
What other medicines interact with Promethazine?
MediHelp also lists interactions of Promethazine with, for example, Ibutilide, Pimozide, Thioridazine. The full list is on the Promethazine page.
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