Ranunculus sceleratus 石龍芮

Ranunculaceae 毛茛科

Celery-leaved Crowfoot1

水堇、野芹菜2

POISONOUS PARTS

Whole plant, especially the sap and flowers.3,4

TOXICITY

  • Toxic Constituents
    Protoanemonin (also known as anemonol) and ranunculin.2-5
  • Mechanism
    Ranunculin is hydrolyzed into protoanemonin upon crushing of plant tissue. Protoanemonin is an irritant to skin, eyes and mucosal surface; it binds sulphydryl groups and disrupts disulphide bonds, leading to disruption of skin architecture and formation of bulla.6
  • Poisoning Features
    Skin contact: irritant contact dermatitis. Ingestion: stomatitis, vomiting, diarrhoea, abdominal pain, dizziness, convulsion.3,5,7
  • Poisoning Events
    Cases of irritant contact dermatitis after external application of R. sceleratus as treatment for rheumatoid arthritis and knee pain have been reported in China.8,9

CLINICAL MANAGEMENT

Supportive treatment. For skin exposure, affected area could be irrigated with water. Correction of fluid and electrolyte disturbances in patients with severe gastrointestinal symptoms.3,7

IDENTIFICATION FEATURES

Annual herbs, 10–40 cm tall. Stems erect, glabrous or sparsely puberulent. Basal leaves simple, 1–4 × 1.5–5 cm, long petioled, 3-partite. Cauline leaves many; upper ones smaller, 3-divided. Cymes terminal, flowers 4–8 mm in diameter. Petals 5, yellow, about 3.5 mm long. Aggregate fruits 8–12 mm long; achenes obovoid, slightly compressed.10

MEDICINAL USES

Uses in TCM—whole plant: clear heat and remove toxin, disperse swelling and dissipate binds, relieve pain, control malaria; fruits: harmonise the stomach function, tonify kidney, improve vision, dispel wind-dampness. Recommended dose: whole plant 3–9 g, fruits 3–9 g.2

LABORATORY ANALYSIS

Protoanemonin and ranunculin can be detected by HPLC-DAD and LC-MS/MS respectively.11