Drug interactions
Brompheniramine + Diphenhydramine
Severity: Moderate
Brompheniramine and Diphenhydramine: 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
Two first-generation antihistamines taken together increase sedation, psychomotor impairment and anticholinergic effects. Duplication often occurs with OTC cold and sleep products.
What this interaction means in plain words
Brompheniramine and Diphenhydramine 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.
Brompheniramine belongs to Respiratory; Diphenhydramine belongs to Respiratory.
Why it happens
Additive central H1-receptor antagonism and muscarinic blockade.
What to do
Avoid duplicate antihistamines and check the ingredients of combination products. Take extra care 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 Brompheniramine
Other interactions of Diphenhydramine
Frequently asked questions
Can I take Brompheniramine with Diphenhydramine?
MediHelp rates the interaction as moderate. Brompheniramine and Diphenhydramine 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. Two first-generation antihistamines taken together increase sedation, psychomotor impairment and anticholinergic effects. Duplication often occurs with OTC cold and sleep products.
How serious is the interaction between Brompheniramine and Diphenhydramine?
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 duplicate antihistamines and check the ingredients of combination products. Take extra care in older patients.
What other medicines interact with Brompheniramine?
MediHelp also lists interactions of Brompheniramine with, for example, Alfentanil, Belladonna and opium, Benzhydrocodone / acetaminophen. The full list is on the Brompheniramine page.
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