Drug interactions
Prednisolone + St john's wort
Severity: Moderate
Prednisolone 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 induces CYP3A4 and P-glycoprotein and can lower prednisolone exposure. This may reduce steroid effect and allow underlying disease to flare. The magnitude varies between herbal products.
What this interaction means in plain words
Prednisolone 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 hyperforin increases prednisolone clearance.
What to do
Advise the patient to avoid St John's wort. If it is continued, monitor for loss of steroid effect and adjust the dose, and reassess when the herb is stopped.
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 Prednisolone
- Bcg vaccine live + Prednisolone Contraindicated
- Measles mumps and rubella vaccine live + Prednisolone Contraindicated
- Measles mumps rubella and varicella vaccine live + Prednisolone Contraindicated
- Measles vaccine + Prednisolone Contraindicated
- Mifepristone + Prednisolone Contraindicated
- Prednisolone + Radium-223 dichloride Contraindicated
Frequently asked questions
Can I take Prednisolone with St john's wort?
MediHelp rates the interaction as moderate. Prednisolone 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 induces CYP3A4 and P-glycoprotein and can lower prednisolone exposure. This may reduce steroid effect and allow underlying disease to flare. The magnitude varies between herbal products.
How serious is the interaction between Prednisolone 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 the patient to avoid St John's wort. If it is continued, monitor for loss of steroid effect and adjust the dose, and reassess when the herb is stopped.
What other medicines interact with Prednisolone?
MediHelp also lists interactions of Prednisolone with, for example, Bcg vaccine live, Measles mumps and rubella vaccine live, Measles mumps rubella and varicella vaccine live. The full list is on the Prednisolone page.
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