Drug interactions
Chlorpheniramine + Cyproheptadine
Severity: Moderate
Chlorpheniramine and Cyproheptadine: 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 antihistamines, so combined use duplicates therapy and raises the risk of sedation and anticholinergic effects such as dry mouth, urinary retention and confusion.
What this interaction means in plain words
Chlorpheniramine and Cyproheptadine 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; Cyproheptadine belongs to Respiratory.
Why it happens
Additive H1-receptor antagonism with additive antimuscarinic and CNS depressant effects.
What to do
Avoid concurrent use of two first-generation antihistamines; use one agent and counsel about drowsiness.
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 Cyproheptadine
- Cyproheptadine + Isocarboxazid Contraindicated
- Cyproheptadine + Phenelzine Contraindicated
- Cyproheptadine + Tranylcypromine Contraindicated
- Alfentanil + Cyproheptadine Major
- Belladonna and opium + Cyproheptadine Major
- Benzhydrocodone / acetaminophen + Cyproheptadine Major
Other interactions of Chlorpheniramine
Frequently asked questions
Can I take Chlorpheniramine with Cyproheptadine?
MediHelp rates the interaction as moderate. Chlorpheniramine and Cyproheptadine 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 antihistamines, so combined use duplicates therapy and raises the risk of sedation and anticholinergic effects such as dry mouth, urinary retention and confusion.
How serious is the interaction between Chlorpheniramine and Cyproheptadine?
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 concurrent use of two first-generation antihistamines; use one agent and counsel about drowsiness.
What other medicines interact with Cyproheptadine?
MediHelp also lists interactions of Cyproheptadine with, for example, Isocarboxazid, Phenelzine, Tranylcypromine. The full list is on the Cyproheptadine page.
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