Alligator Weed Herb

Chinese
空心莲子草
Pinyin
Kong Xin Lian Zi Cao
Latin
Herba Alternantherae

TCM Properties

Taste
slightly bitter
Temperature
cool
Channels
Liver, Heart, Lung

Traditional Use

Primary Actions

  • Clears Heat and cools Blood — febrile illness, hemoptysis, hematuria, and epistaxis from Blood Heat
  • Resolves toxicity and reduces swelling — carbuncles, venomous snake bite, and infected sores
  • Clears Lung Heat and stops cough — Lung-heat cough and hemoptysis
  • Promotes urination — dysuria and urinary tract infection from Damp-Heat

Secondary Actions

  • External use for burns and skin conditions — fresh herb pounded as poultice for burns, scalds, and eczematous skin in south China folk medicine
  • Antidiabetic folk use — used in southeast Asian traditional medicine for blood glucose management; validated in preliminary pharmacological studies

Classical References

  • Guang Zhou Min Jian Cao Yao (广州民间草药): documents Kong Xin Lian Zi Cao (空心莲子草, 'hollow-heart lotus-seed herb', named for the hollow stems floating on water) as a Heat-clearing and Blood-cooling herb used in Guangdong and south China folk medicine for febrile bleeding, snake bite, and burns; the plant is semi-aquatic and widely distributed in rice paddies and waterways of tropical and subtropical China
  • SPECIES NOTE: Herb #90 (Kong Xin Lian Zi Cao) is Alternanthera philoxeroides (Mart.) Griseb. — Alligator Weed, an invasive aquatic herb from South America naturalised throughout tropical Asia; Herb #91 (Lian Zi Cao) in this database shares the same Latin Herba Alternantherae and may represent Alternanthera sessilis L. — a related but distinct species; both are used interchangeably under the Herba Alternantherae umbrella in regional folk medicine

Modern Research

Active Compounds

  • Quercetin and kaempferol glycosides (flavonoids; anti-inflammatory, antioxidant)
  • Betacyanins and betaxanthins (betalain pigments; antioxidant, antidiabetic)
  • Triterpenoids: oleanolic acid, ursolic acid (anti-inflammatory, hepatoprotective)
  • Sterols: β-sitosterol, stigmasterol (anti-inflammatory)
  • Phenolic acids: chlorogenic acid, caffeic acid (antioxidant)

Studied Effects

  • Anti-inflammatory: flavonoid and triterpenoid fractions from Alternanthera philoxeroides inhibit COX-2 and NF-κB in LPS-stimulated macrophage models; significant reduction of paw edema in carrageenan assays — provides mechanistic basis for the Heat-clearing and toxin-resolving folk applications
  • Antidiabetic: aqueous extract of A. philoxeroides shows significant glucose-lowering activity in streptozotocin-induced diabetic rodent models via α-glucosidase inhibition and insulin sensitisation; betacyanin content may contribute additional antioxidant protection of pancreatic β-cells — consistent with the southeast Asian folk diabetes application
  • Wound healing and antifungal: topical preparations of A. philoxeroides accelerate wound contraction and re-epithelialisation in excision wound models; aqueous and ethanol extracts inhibit Candida albicans and dermatophytes — supports the folk topical use for burns, skin sores, and skin infections

Safety & Interactions

Contraindications

  • Spleen-Stomach Deficiency Cold — cool nature impairs digestive Yang with prolonged use
  • Cold-pattern bleeding without Blood Heat — cooling action inappropriate for cold-deficiency haemorrhage

Cautions

  • Standard dose: 15–30 g dried herb in decoction; 30–60 g fresh herb; topical: fresh herb pounded as poultice
  • Limited formal clinical safety and pharmacokinetic data; considered safe at traditional doses based on extensive folk use across south China and southeast Asia
  • Antidiabetic medications: additive glucose-lowering effect; monitor blood glucose in diabetic patients consuming regularly

Drug Interactions

  • Antidiabetic medications — additive hypoglycemic effect via α-glucosidase inhibition; monitor blood glucose

Conditions