Drug interactions
Lasmiditan + Promethazine
Severity: Moderate
Lasmiditan 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
Lasmiditan commonly causes dizziness and sedation, and promethazine is strongly sedating, so combined use may increase drowsiness and impair psychomotor function. Combined effects have not been well studied.
What this interaction means in plain words
Lasmiditan 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.
Lasmiditan belongs to Central Nervous System; Promethazine belongs to Respiratory.
Why it happens
Additive CNS depressant effects.
What to do
Warn patients not to drive or operate machinery for at least 8 hours after lasmiditan and to be cautious with other sedatives. Monitor for excessive sedation and consider an alternative antiemetic if it occurs.
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 Lasmiditan
- Alprazolam + Lasmiditan Moderate
- Amiodarone + Lasmiditan Moderate
- Amisulpride + Lasmiditan Moderate
- Amobarbital + Lasmiditan Moderate
- Aripiprazole + Lasmiditan Moderate
- Asenapine + Lasmiditan Moderate
Frequently asked questions
Can I take Lasmiditan with Promethazine?
MediHelp rates the interaction as moderate. Lasmiditan 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. Lasmiditan commonly causes dizziness and sedation, and promethazine is strongly sedating, so combined use may increase drowsiness and impair psychomotor function. Combined effects have not been well studied.
How serious is the interaction between Lasmiditan 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: Warn patients not to drive or operate machinery for at least 8 hours after lasmiditan and to be cautious with other sedatives. Monitor for excessive sedation and consider an alternative antiemetic if it occurs.
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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