POISONOUS PARTS
Whole plant, especially the seeds.4,5
TOXICITY
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Toxic Constituents
Pharbitin and ergot alkaloids such as chanoclavine, elymoclavine and penniclavine.6,7
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Toxic Dose
1–2 g/kg seeds can induce hallucination.8
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Mechanism
Various ergot alkaloids can modulate the activities of serotonin, dopamine and noradrenaline receptors. Pharbitin, a resin glycoside, may be implicated in the nephrotoxicity upon chronic ingestion of the seeds. The exact mechanism is unidentified.8,9
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Poisoning Features
Vomiting, diarrhoea, abdominal pain, hallucination and delirium. Renal impairment in long term use.6,8-11
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Poisoning Events
An 18-month-old girl in China developed vomiting, diarrhoea, agitation and other neurological symptoms after taking 50 g of the seeds as a medication for abdominal bloating. She recovered uneventfully after treatment.12
CLINICAL MANAGEMENT
Supportive treatment.
IDENTIFICATION FEATURES
Annual twining herbs. Stems 2–5 m long, retrorsely hirsute. Leaf blades 4–15 × 4.5–14 cm, often 3(or 5) lobed, hirtellous. Cymes 1–several flowered. Sepals 1–2.5 cm long, abaxially spreading hirsute. Corolla pale to bright blue with whitish tube, 5–6(–8) cm long, funnelform. Stamens and pistil inclusive. Capsules straw coloured, 8–10 mm in diameter. Seeds 5–6 mm long, black, grey puberulent.13
MEDICINAL USES
Seeds used in TCM: induce diuresis, relieve constipation, dispel phlegm and expel retained fluid, kill parasites. Recommended dose: 3–10 g.6,14
LABORATORY ANALYSIS
Chanoclavine and elymoclavine can be detected by LC-MS/MS.15
