Drug interactions
Clemastine + Dexchlorpheniramine
Severity: Moderate
Clemastine and Dexchlorpheniramine: 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 first-generation sedating antihistamines, so the combination duplicates therapy and increases drowsiness and anticholinergic effects. Dry mouth, urinary retention and confusion are more likely, particularly in older adults.
What this interaction means in plain words
Clemastine and Dexchlorpheniramine 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.
Clemastine belongs to Respiratory; Dexchlorpheniramine belongs to Respiratory.
Why it happens
Therapeutic duplication with additive H1 blockade and anticholinergic activity.
What to do
Avoid combining two sedating antihistamines and use a single agent. Monitor for sedation and anticholinergic toxicity if both were taken.
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 Clemastine
Other interactions of Dexchlorpheniramine
- Alprazolam + Dexchlorpheniramine Moderate
- Amisulpride + Dexchlorpheniramine Moderate
- Amitriptyline + Dexchlorpheniramine Moderate
- Amobarbital + Dexchlorpheniramine Moderate
- Asenapine + Dexchlorpheniramine Moderate
- Azelastine-fluticasone + Dexchlorpheniramine Moderate
Frequently asked questions
Can I take Clemastine with Dexchlorpheniramine?
MediHelp rates the interaction as moderate. Clemastine and Dexchlorpheniramine 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 first-generation sedating antihistamines, so the combination duplicates therapy and increases drowsiness and anticholinergic effects. Dry mouth, urinary retention and confusion are more likely, particularly in older adults.
How serious is the interaction between Clemastine and Dexchlorpheniramine?
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 two sedating antihistamines and use a single agent. Monitor for sedation and anticholinergic toxicity if both were taken.
What other medicines interact with Clemastine?
MediHelp also lists interactions of Clemastine with, for example, Alfentanil, Benzhydrocodone / acetaminophen, Buprenorphine buccal. The full list is on the Clemastine page.
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