Drug interactions
Cimetidine + Eucalyptus
Severity: Minor
Cimetidine and Eucalyptus: 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
Eucalyptus oil is metabolized by CYP enzymes, so cimetidine could increase its levels. Clinical evidence is lacking and effects are theoretical.
What this interaction means in plain words
Cimetidine and Eucalyptus have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Why it happens
Theoretical CYP3A4 inhibition by cimetidine reducing metabolism of eucalyptus constituents.
What to do
No specific action is needed; avoid ingesting eucalyptus oil, which is toxic in large amounts.
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?
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Other interactions of Cimetidine
- Cimetidine + Dofetilide Contraindicated
- Cimetidine + Fezolinetant Contraindicated
- Alfentanil + Cimetidine Major
- Atazanavir + Cimetidine Major
- Carmustine + Cimetidine Major
- Cimetidine + Citalopram Major
Frequently asked questions
Can I take Cimetidine with Eucalyptus?
MediHelp rates the interaction as minor. Cimetidine and Eucalyptus have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Eucalyptus oil is metabolized by CYP enzymes, so cimetidine could increase its levels. Clinical evidence is lacking and effects are theoretical.
How serious is the interaction between Cimetidine and Eucalyptus?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: No specific action is needed; avoid ingesting eucalyptus oil, which is toxic in large amounts.
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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