St Johns Wort × Simvastatin

Severity: MODERATE Evidence: well-established

Mechanism

St. John's wort induces CYP3A4, increasing simvastatin metabolism.

Effect

Reduced simvastatin levels; loss of lipid-lowering effect

Management

Monitor lipid levels. May need dose adjustment or switch to pravastatin.

Source

Sugimoto K et al. Clin Pharmacol Ther 2001

⚠️ MODERATE INTERACTION: Monitor closely if this combination is used.

Disclaimer

This interaction record is for informational purposes only and does not constitute medical advice. Always consult a healthcare provider before starting or stopping any supplement or medication.