Shepherd's Purse Herb — Safety & Interactions

Ji Cai · Herba Capsellae

Contraindications

  • Pregnancy — acetylcholine and choline content stimulate uterine contractions; traditionally contraindicated in pregnancy due to uterotonic activity
  • Cold-pattern bleeding without Heat signs (pale blood, cold abdomen, no fever) — cool-natured herb would worsen Cold deficiency bleeding

Cautions

  • Standard dose: 15–30 g dried herb in decoction; 30–60 g fresh herb
  • Anticoagulant medications (warfarin): high vitamin K1 content may reduce anticoagulant efficacy — monitor INR if consumed regularly in large quantities as a food herb
  • Thyroid medications: very high daily intake (well above therapeutic doses) of glucosinolate-containing Brassicaceae plants may theoretically affect thyroid hormone synthesis; not a concern at standard therapeutic doses
  • Generally considered safe at culinary and standard therapeutic doses based on millennia of continuous use as a vegetable across East Asia and the Mediterranean

Drug Interactions

Drug Class / Substrate Mechanism Severity Source
Warfarin and vitamin K antagonists — regular high-dose consumption may reduce anticoagulant effect via vitamin K1 content; monitor INR

Pregnancy

Not recommended during pregnancy. Consult a qualified practitioner before any use.

This information is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before using herbal medicines, especially if you take prescription medications.