Plumbago zeylanica 白花丹

Plumbaginaceae 白花丹科

White Leadwort¹

白雪花、烏面馬²

POISONOUS PARTS

Roots and leaves.^3,4

TOXICITY

Toxic Constituents
Plumbagin.^3–5
Mechanism
Plumbagin is cytotoxic. It increases the formation of reactive oxygen species in cells, leading to DNA strand breakage and base damage.⁶
Poisoning Features
Skin contact: contact dermatitis, stinging pain, blistering. Ingestion: vomiting, diarrhoea, miscarriage.^3–5,7–9

CLINICAL MANAGEMENT

Supportive treatment. Activated charcoal therapy has been used for gastrointestinal decontamination in P. zeylanica poisoning. For skin exposure, affected area could be irrigated with water.⁵

IDENTIFICATION FEATURES

Semi-climbing subshrubs, 1–2 m tall. Leaves alternate, or sometimes in cluster of 3 unequal on branches; leaf blades 3–10 × 2–2.5 cm. Spikes 8–17 cm long; rhachis glandular. Calyx-tubes about 1.1 cm long, 5-ribbed, with glandular hairs. Corolla white or bluish; tubes 1.7–2 cm long; lobes about 5 mm long, spreading. Style single, 5-lobed at apex. Capsules 5–7 mm long.¹⁰

MEDICINAL USES

Whole plant or roots used in TCM: dispel wind-dampness, dissipate stasis and disperse swelling, move qi and activate blood, remove toxin, kill parasites. Recommended dose: 9–15 g. Generally, do not apply for more than 30 minutes when used externally.^2,11,12

CASES IN TRL

In 2016, a middle-aged man developed stinging pain and skin changes on his foot, 3–4 hours after external application of self-made herbal poultice. The poultice, aimed to treat foot sore, was prepared from blending 20 pieces of fresh leaves of “Dujiaolian” picked from the countryside and other TCM. The patient recovered with supportive management. The left-over plant (photo A) was morphologically identified as P. zeylanica.