Drug interactions
Cinnarizine + Promethazine
Severity: Moderate
Cinnarizine 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
Cinnarizine is a sedating antihistamine and calcium channel blocker, and it can cause drowsiness and, uncommonly, extrapyramidal effects. Combining it with promethazine increases sedation and anticholinergic effects.
What this interaction means in plain words
Cinnarizine 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.
Cinnarizine belongs to Respiratory; Promethazine belongs to Respiratory.
Why it happens
Additive H1 antihistaminic and CNS depressant effects.
What to do
Avoid combining the two for the same indication, such as nausea or vertigo. Monitor for oversedation and extrapyramidal symptoms in older patients.
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
- Cabergoline + Promethazine Contraindicated
- Dopamine + Promethazine Contraindicated
- Ibutilide + Promethazine Contraindicated
- Pimozide + Promethazine Contraindicated
- Promethazine + Thioridazine Contraindicated
- Alfentanil + Promethazine Major
Other interactions of Cinnarizine
- Alprazolam + Cinnarizine Moderate
- Amitriptyline + Cinnarizine Moderate
- Amobarbital + Cinnarizine Moderate
- Aripiprazole + Cinnarizine Moderate
- Azelastine-fluticasone + Cinnarizine Moderate
- Azelastine + Cinnarizine Moderate
Frequently asked questions
Can I take Cinnarizine with Promethazine?
MediHelp rates the interaction as moderate. Cinnarizine 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. Cinnarizine is a sedating antihistamine and calcium channel blocker, and it can cause drowsiness and, uncommonly, extrapyramidal effects. Combining it with promethazine increases sedation and anticholinergic effects.
How serious is the interaction between Cinnarizine 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: Avoid combining the two for the same indication, such as nausea or vertigo. Monitor for oversedation and extrapyramidal symptoms in older patients.
What other medicines interact with Promethazine?
MediHelp also lists interactions of Promethazine with, for example, Cabergoline, Dopamine, Ibutilide. The full list is on the Promethazine page.
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