Sweet Wormwood Herb — Safety & Interactions
Huang Hao · Herba Artemisiae Annuae
Use with caution. Practitioner review recommended before use.
Contraindications
- Spleen-Stomach Deficiency Cold — cold-bitter nature strongly contraindicated with chronic diarrhea, cold abdomen, and digestive weakness; can cause severe nausea and vomiting
- Malaria monotherapy: artemisinin should never be used as monotherapy for malaria — WHO mandates artemisinin combination therapy (ACT) to prevent resistance emergence
Cautions
- Standard TCM dose (whole herb decoction): 6–12 g, added near the end of decocting to preserve volatile oil; do not boil prolongedly — artemisinin is heat-labile and significantly degraded by prolonged cooking (hence Ge Hong's cold-water extraction instruction)
- Pregnancy: artemisinin derivatives are embryotoxic in animal studies in the first trimester; WHO advises against use in first trimester unless benefit outweighs risk for severe malaria; avoid in pregnancy for non-malarial indications
- CYP2B6 and CYP3A4 induction: artemisinin is a potent auto-inducer of its own metabolism (CYP2B6) and induces CYP3A4 — reduces plasma levels of CYP3A4-substrate drugs (statins, immunosuppressants, antiretrovirals, oral contraceptives) with repeated dosing
- QT interval: high-dose artemether-lumefantrine combinations may prolong QT; avoid with other QT-prolonging drugs
- Do not confuse with Yin Chen Hao (茵陈蒿, A. capillaris — jaundice herb) or Ai Ye (艾叶, A. argyi — moxibustion herb); these are distinct drugs with different indications
Drug Interactions
| Drug Class / Substrate | Mechanism | Severity | Source |
|---|---|---|---|
| CYP3A4 substrates (statins, immunosuppressants, antiretrovirals, oral contraceptives) — artemisinin induces CYP3A4; reduced plasma drug levels with repeated dosing | |||
| CYP2B6 substrates (efavirenz, bupropion, cyclophosphamide) — artemisinin induces CYP2B6; monitor for reduced efficacy | |||
| QT-prolonging medications — additive QT prolongation risk with artemether-based formulations | |||
| Anticoagulants — artemisinin derivatives may affect vitamin K metabolism; monitor INR with warfarin | |||
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.