Herb-Drug Interaction Checker

Check for potential interactions between herbal products and medications

Evidence-Based Regularly Updated Clinical Grade
Important Disclaimer:

This tool is for informational purposes only and does not constitute medical advice. Always consult a healthcare professional before combining herbal products with medications. The absence of an interaction in our database does not guarantee safety.

Search by Latin name, common name, or plant
Search by drug name (active ingredient)
— or enter custom names —
Quick lookup: St. John's Wort Ginkgo Ginseng Echinacea Valerian

Understanding Severity Levels

Our database classifies herb-drug interactions into four severity levels based on clinical significance.

Critical

Life-threatening or permanent damage possible

  • Avoid combination entirely
  • Immediate medical attention if taken together
  • No safe alternatives exist
Contraindicated
Severe

Significant harm or hospitalization risk

  • Generally avoid this combination
  • Only use with close medical supervision
  • Requires dosage adjustments
Medical supervision required
Moderate

Could worsen condition or require treatment changes

  • Use with caution
  • Monitor for adverse effects
  • Inform your healthcare provider
Monitoring recommended
Mild

Minor effects, usually well-tolerated

  • Generally safe with awareness
  • May require timing adjustments
  • Watch for minor symptoms
Usually manageable

Common Herb-Drug Interactions

Critical/Severe
  • St. John's Wort + Immunosuppressants
    Organ rejection risk (transplant patients)
  • St. John's Wort + HIV medications
    Reduced antiviral efficacy
  • Ginkgo + Anticoagulants
    Serious bleeding risk
Severe
  • St. John's Wort + SSRIs
    Serotonin syndrome risk
  • Grapefruit + Statins
    Muscle damage (rhabdomyolysis)
  • Licorice + Digoxin
    Cardiac arrhythmia risk
Moderate
  • Ginseng + Anticoagulants
    May affect platelet function
  • Echinacea + Immunosuppressants
    May reduce effectiveness
  • Valerian + CNS Depressants
    Additive sedation
Mild
  • Chamomile + Anticoagulants
    Slight bleeding risk increase
  • Green Tea + Iron supplements
    Reduced iron absorption
  • Milk Thistle + Some drugs
    Mild CYP enzyme effects
How Interactions Occur
  • Pharmacokinetic: Affecting absorption, distribution, metabolism, or excretion
  • Pharmacodynamic: Additive, synergistic, or antagonistic effects at the same target
  • CYP450 Enzymes: Many herbs affect these drug-metabolizing enzymes
  • P-glycoprotein: Some herbs affect this drug transporter
Safety Recommendations
  • Always inform your doctor about herbal products you use
  • Stop herbal products 2 weeks before surgery
  • Be cautious with herbs affecting blood clotting
  • Watch for signs of unexpected drug effects
  • Keep a complete medication and supplement list