Drug interactions
Cyproheptadine + Trifluoperazine
Severity: Moderate
Cyproheptadine and Trifluoperazine: 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
Cyproheptadine is a sedating first-generation antihistamine and trifluoperazine is a phenothiazine antipsychotic with sedative and anticholinergic properties. Taken together they can cause greater drowsiness, impaired psychomotor performance and additive anticholinergic effects such as dry mouth, constipation and urinary retention.
What this interaction means in plain words
Cyproheptadine and Trifluoperazine 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 and anticholinergic effects through histamine H1, muscarinic and dopamine receptor blockade.
What to do
Monitor for excessive sedation and anticholinergic toxicity, particularly in elderly patients, and reduce the dose of one agent if symptoms develop. Advise patients to avoid driving and alcohol.
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
Frequently asked questions
Can I take Cyproheptadine with Trifluoperazine?
MediHelp rates the interaction as moderate. Cyproheptadine and Trifluoperazine 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. Cyproheptadine is a sedating first-generation antihistamine and trifluoperazine is a phenothiazine antipsychotic with sedative and anticholinergic properties. Taken together they can cause greater drowsiness, impaired psychomotor performance and additive anticholinergic effects such as dry mouth, constipation and urinary retention.
How serious is the interaction between Cyproheptadine and Trifluoperazine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor for excessive sedation and anticholinergic toxicity, particularly in elderly patients, and reduce the dose of one agent if symptoms develop. Advise patients to avoid driving and alcohol.
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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