St Johns Wort × Theophylline

Severity: MODERATE Evidence: probable

Mechanism

St. John's wort induces CYP1A2, increasing theophylline metabolism.

Effect

Reduced theophylline levels; loss of bronchodilation

Management

Monitor theophylline levels. May need dose increase.

Source

Nebel A et al. Clin Pharmacol Ther 1999

⚠️ 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.