Senna siamea 鐵刀木

Caesalpiniaceae 蘇木科

Kassod Tree1

黑心樹2

POISONOUS PARTS

Roots, bark and leaves.3

TOXICITY

  • Toxic Constituents
    Irritants in sawdust, barakol and anthraquinones such as emodin and chrysophanol.3–7
  • Toxic Dose
    Intake of herbal capsules containing a total of 60 mg barakol (equivalent to 2400 mg dried leaf powder) over 3 days can be hepatotoxic.6,8
  • Mechanism
    Sawdust is an irritant to skin and eyes. Barakol has anxiolytic and hypnotic effects, and is probably hepatotoxic; the exact mechanism is unidentified. Anthraquinones have purgative effect.3–6,8,9
  • Poisoning Features
    Skin contact: irritant contact dermatitis. Eye contact: keratoconjunctivitis. Ingestion: diarrhoea, acute hepatitis.3–6,8
  • Poisoning Events
    S. siamea leaf capsule (each contains 400 mg dried leaf powder, equivalent to 10 mg barakol) was once marketed in Thailand as a herbal hypnotic but was withdrawn in 2003 due to hepatotoxicity. One report described 12 cases of acute hepatitis after taking 2–4 capsules per day for 3–180 days. All patients recovered after treatment.6,8

CLINICAL MANAGEMENT

Supportive treatment. For skin and ocular exposure, affected area could be irrigated with water.3,8

IDENTIFICATION FEATURES

Evergreen trees, up to 10 m tall; trunk nearly smooth, bark slightly fissured. Petioles base swollen, petioles and rachises puberculent, rachises with longitudinal grooves. Leaflets 6–10 pairs, 3–6.5 × 1.5–2.5 cm, whitish green abaxially, apex mucronate. Corymbose racemes axillary; petals yellow, 1.2–1.4 cm long. Pods 15–30 × 1–1.5 cm, 10–20-seeded.10

MEDICINAL USES

In Southeast Asia, leaves have been used in folk medicine as laxative; besides, somnolent, antipyretic and antihypertensive effects have also been shown.5

LABORATORY ANALYSIS

Anthraquinones can be detected by HPLC-DAD, GC-MS and LC-MS/MS. Barakol can be detected by HPLC-ECD and TLC-Densitometry.11–15