Drug interactions
Oxazepam + Promethazine
Severity: Moderate
Oxazepam 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 depress the central nervous system, so combined use increases drowsiness, impaired coordination and fall risk. Effects are more pronounced in older adults and with alcohol.
What this interaction means in plain words
Oxazepam 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.
Oxazepam belongs to Central Nervous System; Promethazine belongs to Respiratory.
Why it happens
Additive CNS depression via GABA-A enhancement and H1 antagonism.
What to do
Use the lowest effective doses and counsel on avoiding driving and alcohol. Monitor older patients for oversedation.
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 Oxazepam
- Calcium / magnesium / potassium / sodium oxybates + Oxazepam Contraindicated
- Oxazepam + Sodium oxybate Contraindicated
- Alfentanil + Oxazepam Major
- Amobarbital + Oxazepam Major
- Baclofen + Oxazepam Major
- Belladonna and opium + Oxazepam Major
Frequently asked questions
Can I take Oxazepam with Promethazine?
MediHelp rates the interaction as moderate. Oxazepam 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 depress the central nervous system, so combined use increases drowsiness, impaired coordination and fall risk. Effects are more pronounced in older adults and with alcohol.
How serious is the interaction between Oxazepam 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 counsel on avoiding driving and alcohol. Monitor older patients for oversedation.
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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