Drug interactions
Chlorpheniramine + Diazepam intranasal
Severity: Moderate
Chlorpheniramine and Diazepam intranasal: 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
Chlorpheniramine can add to the CNS depressant effects of diazepam, increasing drowsiness, dizziness and impaired coordination. Respiratory depression is possible at higher exposures.
What this interaction means in plain words
Chlorpheniramine and Diazepam intranasal 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.
Why it happens
Additive CNS depression from benzodiazepine GABA-A potentiation and sedating H1 blockade.
What to do
Advise against driving and alcohol use, and monitor for oversedation after diazepam doses. Prefer a non-sedating antihistamine when feasible.
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 Chlorpheniramine
Frequently asked questions
Can I take Chlorpheniramine with Diazepam intranasal?
MediHelp rates the interaction as moderate. Chlorpheniramine and Diazepam intranasal 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. Chlorpheniramine can add to the CNS depressant effects of diazepam, increasing drowsiness, dizziness and impaired coordination. Respiratory depression is possible at higher exposures.
How serious is the interaction between Chlorpheniramine and Diazepam intranasal?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Advise against driving and alcohol use, and monitor for oversedation after diazepam doses. Prefer a non-sedating antihistamine when feasible.
What other medicines interact with Chlorpheniramine?
MediHelp also lists interactions of Chlorpheniramine with, for example, Belladonna and opium, Benzhydrocodone / acetaminophen, Brexanolone. The full list is on the Chlorpheniramine page.
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