Drug interactions
Dantrolene + Promethazine
Severity: Moderate
Dantrolene 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
Dantrolene commonly causes drowsiness, dizziness and weakness, and promethazine is strongly sedating. Using them together can intensify central nervous system depression and impair alertness and coordination.
What this interaction means in plain words
Dantrolene 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.
Dantrolene belongs to Musculoskeletal; Promethazine belongs to Respiratory.
Why it happens
Additive CNS depressant effects through different pharmacodynamic pathways.
What to do
Start with reduced doses of one or both agents and monitor for excessive sedation and muscle weakness. Advise patients to avoid driving and alcohol.
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 Dantrolene
Frequently asked questions
Can I take Dantrolene with Promethazine?
MediHelp rates the interaction as moderate. Dantrolene 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. Dantrolene commonly causes drowsiness, dizziness and weakness, and promethazine is strongly sedating. Using them together can intensify central nervous system depression and impair alertness and coordination.
How serious is the interaction between Dantrolene 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: Start with reduced doses of one or both agents and monitor for excessive sedation and muscle weakness. Advise patients to avoid driving and alcohol.
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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