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Drug interactions

Cimetidine + Trifluoperazine

Severity: Minor

Cimetidine and Trifluoperazine: minor 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

Cimetidine may raise trifluoperazine levels by reducing its metabolism, possibly increasing sedation and extrapyramidal effects.

What this interaction means in plain words

Cimetidine and Trifluoperazine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.

Evidence level: Low

Why it happens

Cimetidine inhibits CYP enzymes, including CYP2D6, involved in phenothiazine metabolism.

What to do

Monitor for sedation, extrapyramidal symptoms and hypotension, and lower the trifluoperazine dose if they occur.

What to ask your pharmacist

  • Is there anything I should notice while taking both?
  • Do I need to tell my doctor at the next visit?

Bring a full list of your medicines, including over-the-counter products, supplements and herbal remedies, to every pharmacy visit.

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Frequently asked questions

Can I take Cimetidine with Trifluoperazine?

MediHelp rates the interaction as minor. Cimetidine and Trifluoperazine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Cimetidine may raise trifluoperazine levels by reducing its metabolism, possibly increasing sedation and extrapyramidal effects.

How serious is the interaction between Cimetidine and Trifluoperazine?

MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor for sedation, extrapyramidal symptoms and hypotension, and lower the trifluoperazine dose if they occur.

What other medicines interact with Cimetidine?

MediHelp also lists interactions of Cimetidine with, for example, Dofetilide, Fezolinetant, Alfentanil. The full list is on the Cimetidine page.

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