Drug interactions
Red yeast rice + St john's wort
Severity: Moderate
Red yeast rice 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, which metabolizes monacolin K (lovastatin). This may lower exposure and reduce the cholesterol-lowering effect of red yeast rice.
What this interaction means in plain words
Red yeast rice 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
St John's wort induces CYP3A4 and P-glycoprotein, increasing clearance of monacolin K.
What to do
Monitor the lipid profile and consider avoiding the combination if lipid control is important. Reassess lipids after starting or stopping St John's wort.
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 Red yeast rice
- Red yeast rice + Ritonavir Contraindicated
- Red yeast rice + Saquinavir Contraindicated
- Red yeast rice + Tipranavir Contraindicated
- Atazanavir + Red yeast rice Major
- Atorvastatin + Red yeast rice Major
- Conivaptan + Red yeast rice Major
Frequently asked questions
Can I take Red yeast rice with St john's wort?
MediHelp rates the interaction as moderate. Red yeast rice 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, which metabolizes monacolin K (lovastatin). This may lower exposure and reduce the cholesterol-lowering effect of red yeast rice.
How serious is the interaction between Red yeast rice 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: Monitor the lipid profile and consider avoiding the combination if lipid control is important. Reassess lipids after starting or stopping St John's wort.
What other medicines interact with Red yeast rice?
MediHelp also lists interactions of Red yeast rice with, for example, Ritonavir, Saquinavir, Tipranavir. The full list is on the Red yeast rice page.
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