Drug interactions
St john's wort + Tinidazole
Severity: Moderate
St john's wort and Tinidazole: 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
St John's wort induces drug-metabolising enzymes and may lower tinidazole exposure. Reduced concentrations could lead to weaker antimicrobial or antiprotozoal effect and possible treatment failure.
What this interaction means in plain words
St john's wort and Tinidazole 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
Induction of CYP3A4 (and possibly P-glycoprotein) by hyperforin increases tinidazole clearance.
What to do
Avoid St John's wort during tinidazole therapy where possible, or monitor for clinical response and consider an alternative regimen if the infection is not resolving.
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 Tinidazole
- Disulfiram + Tinidazole Contraindicated
- Ethanol + Tinidazole Major
- Fexinidazole + Tinidazole Major
- Lopinavir + Tinidazole Major
- Nilotinib + Tinidazole Major
- Ritonavir + Tinidazole Major
Frequently asked questions
Can I take St john's wort with Tinidazole?
MediHelp rates the interaction as moderate. St john's wort and Tinidazole 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. St John's wort induces drug-metabolising enzymes and may lower tinidazole exposure. Reduced concentrations could lead to weaker antimicrobial or antiprotozoal effect and possible treatment failure.
How serious is the interaction between St john's wort and Tinidazole?
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 St John's wort during tinidazole therapy where possible, or monitor for clinical response and consider an alternative regimen if the infection is not resolving.
What other medicines interact with Tinidazole?
MediHelp also lists interactions of Tinidazole with, for example, Disulfiram, Ethanol, Fexinidazole. The full list is on the Tinidazole page.
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