Abrus precatorius 相思子

Fabaceae 蝶形花科

Rosary Pea¹

相思藤、小人草、紅珠木、紅豆、雞母珠^2,3

POISONOUS PARTS

Seeds.⁴

TOXICITY

Toxic Constituents
Abrin.^5,6
Toxic Dose
1 seed chewed and swallowed can be toxic. As the seed coat is not easily digested, the toxicity is lower when seeds are swallowed whole. Estimated lethal dose of abrin: 0.1–1 µg/kg.⁵
Mechanism
Abrin is released if the seeds are chewed, crushed or drilled (in beadwork). Abrin, a toxalbumin, inactivates ribosome and hence inhibits protein synthesis.⁵
Poisoning Features
Nausea, vomiting, diarrhoea, abdominal pain, gastrointestinal bleeding, tachycardia, drowsiness, hallucination, weakness, convulsion and death. Occasionally, renal failure, pulmonary oedema, respiratory depression , pancreatitis and liver impairment have also been reported.^5,6
Poisoning Events
Multiple cases of abrin poisoning due to suicidal attempt or accidental ingestion of seeds (both used in beadwork and self-picked) in children, have been reported worldwide.^4,5,7–9

CLINICAL MANAGEMENT

Supportive treatment. Correction of fluid and electrolyte disturbances. Activated charcoal therapy has been used for gastrointestinal decontamination in abrin poisoning, but the benefit is uncertain.^5,6

IDENTIFICATION FEATURES

Climbing shrubs, minutely white strigose. Leaves even-pinnate, 10–15 cm long; leaflets 8–15 pairs, membranous, 10–22 × 4–6 mm, apex apiculate. Racemes axillary, 3–6 cm long. Corolla purplish, vexillum broadly ovate, wings and keel very narrow. Pods 2.5–3 × 1–1.5 cm, inflated, densely strigose, valves leathery. Seeds 5–6 mm long, scarlet with a black spot on one side.¹⁰

MEDICINAL USES

Highly toxic; use with caution. Seeds used in TCM: remove toxin, kill parasites. For external use only.^2,11

CASES IN TRL

A middle aged woman was admitted with acute renal failure after drinking a herbal broth prepared with some “touch-me-not“ (Mimosa pudica) collected from the countryside. The plant specimen was later identified as A. precatorius. She required haemodialysis and intensive care for several weeks.