Drug interactions
Prednisone + St john's wort
Severity: Moderate
Prednisone and St john's wort: 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 can reduce corticosteroid exposure and efficacy. Loss of disease control or inadequate replacement may result.
What this interaction means in plain words
Prednisone and St john's wort 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 P-glycoprotein by St John's wort increases corticosteroid clearance.
What to do
Advise patients to avoid St John's wort. If it is continued, monitor clinical response and adjust the prednisone dose.
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 Prednisone
- Bcg vaccine live + Prednisone Contraindicated
- Measles vaccine + Prednisone Contraindicated
- Mifepristone + Prednisone Contraindicated
- Prednisone + Radium-223 dichloride Contraindicated
- Prednisone + Smallpox vaccine live Contraindicated
- Adenovirus types 4 and 7 live + Prednisone Major
Frequently asked questions
Can I take Prednisone with St john's wort?
MediHelp rates the interaction as moderate. Prednisone and St john's wort 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 can reduce corticosteroid exposure and efficacy. Loss of disease control or inadequate replacement may result.
How serious is the interaction between Prednisone and St john's wort?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Advise patients to avoid St John's wort. If it is continued, monitor clinical response and adjust the prednisone dose.
What other medicines interact with Prednisone?
MediHelp also lists interactions of Prednisone with, for example, Bcg vaccine live, Measles vaccine, Mifepristone. The full list is on the Prednisone page.
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