Drug interactions
Chlorpheniramine + Dimenhydrinate
Severity: Moderate
Chlorpheniramine and Dimenhydrinate: 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
Dimenhydrinate contains diphenhydramine, so combining it with chlorpheniramine duplicates sedating antihistamine therapy. Drowsiness and anticholinergic effects such as confusion and urinary retention are increased.
What this interaction means in plain words
Chlorpheniramine and Dimenhydrinate 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 belongs to Respiratory; Dimenhydrinate belongs to Respiratory.
Why it happens
Additive H1-receptor antagonism and anticholinergic and CNS depressant effects.
What to do
Avoid using both together and select a single agent. Counsel on impaired alertness and monitor older patients for anticholinergic effects.
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
Other interactions of Dimenhydrinate
Frequently asked questions
Can I take Chlorpheniramine with Dimenhydrinate?
MediHelp rates the interaction as moderate. Chlorpheniramine and Dimenhydrinate 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. Dimenhydrinate contains diphenhydramine, so combining it with chlorpheniramine duplicates sedating antihistamine therapy. Drowsiness and anticholinergic effects such as confusion and urinary retention are increased.
How serious is the interaction between Chlorpheniramine and Dimenhydrinate?
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 both together and select a single agent. Counsel on impaired alertness and monitor older patients for anticholinergic effects.
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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