Drug interactions
Promethazine + Triprolidine
Severity: Moderate
Promethazine and Triprolidine: 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 are sedating first-generation antihistamines, so using them together duplicates therapy and increases drowsiness, anticholinergic effects and impaired psychomotor performance.
What this interaction means in plain words
Promethazine and Triprolidine 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.
Promethazine belongs to Respiratory; Triprolidine belongs to Respiratory.
Why it happens
Additive H1 receptor antagonism with additive CNS depression and anticholinergic effects.
What to do
Avoid using two sedating antihistamines together and choose one agent. Warn the patient against 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 Triprolidine
Frequently asked questions
Can I take Promethazine with Triprolidine?
MediHelp rates the interaction as moderate. Promethazine and Triprolidine 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 are sedating first-generation antihistamines, so using them together duplicates therapy and increases drowsiness, anticholinergic effects and impaired psychomotor performance.
How serious is the interaction between Promethazine and Triprolidine?
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 using two sedating antihistamines together and choose one agent. Warn the patient against 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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