St Johns Wort × Verapamil

Severity: MODERATE Evidence: probable

Mechanism

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

Effect

Reduced verapamil levels; loss of blood pressure/heart rate control

Management

Monitor blood pressure and heart rate. May need dose adjustment.

Source

Dresser GK et al. Clin Pharmacol Ther 2003

⚠️ 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.