Stephania sinica 汝蘭

Menispermaceae 防己科

華千金藤、金不換、山烏龜¹

POISONOUS PARTS

Roots.^2,3

TOXICITY

Toxic Constituents
Tetrahydropalmatine.^3–5
Toxic Dose
1500 mg of tetrahydropalmatine.⁶
Mechanism
Tetrahydropalmatine downregulates the expression of mammalian target of rapamycin (mTOR), and leads to apoptosis of hepatocytes.⁷
Poisoning Features
Fever, nausea, vomiting, diarrhoea, abdominal pain, Jaundice, hepatomegaly, liver impairment, drowsiness, weakness and central nervous system depression.^4–6,8

CLINICAL MANAGEMENT

Supportive treatment. Activated charcoal therapy has been used for gastrointestinal decontamination in S. sinica poisoning.⁴

IDENTIFICATION FEATURES

Deciduous vines, slightly fleshy; branches with longitudinally striate. Petioles up to 30 cm long. Leaves peltate; leaf blades 10–15 cm or longer. Umbelliform cymes axillary. Male flowers: sepals 6, 1–1.3 mm long; petals 3–4, about 0.8 mm long, with 2 large glands; synandrium 0.7–0.8 mm long. Female flowers: sepal 1; petals 2, glands not conspicuous. Drupes 6–7 mm long.⁹

MEDICINAL USES

Tuberous roots used in TCM: clear heat and remove toxin, invigorate the stomach and relieve pain, dissipate stasis and disperse swelling. Recommended dose: 9–15 g. In addition, levo-tetrahydropalmatine extracted from the plant is marketed to relieve insomnia.^1,4,6,10

CASES IN TRL

In 2005, 3 members from the same family presented with nausea, vomiting, diarrhoea and abdominal pain after taking soup made with the Chinese herb "Fangji". Tetrahydropalmatine was subsequently detected in the blood, urine and leftover herb specimens of these patients, and the herb was later identified as S. sinica.¹¹