Li Lu 藜芦 — Chinese Herbal Medicine

Li Lu (藜芦) At a Glance

• Herb: Li Lu
• Chinese name: 藜芦 (Li Lu)
• Latin name: Veratri Nigri Radix et Rhizoma
• Nature: Cold
• Taste: Acrid, Bitter
• Meridian: Lung
• Category: Resolve Phlegm Heat

Li Lu (藜芦) is a strongly toxic herb classified under the phlegm-resolving category, primarily used to induce emesis and dislodge stubborn phlegm obstructing the throat or chest. Its acrid, bitter, and cold nature drives upward and outward, making it effective for acute phlegm-wind patterns and topical parasitic conditions. Due to significant toxicity, internal use is rare in modern clinical practice and strictly dose-controlled.

Actions & Therapeutic Effects

• Induces vomiting to expel phlegm accumulation in the chest and throat
• Opens the orifices and dispels wind-phlegm obstructing the heart and mind
• Kills parasites and resolves toxicity (topical use for scabies, tinea, and head lice)
• Disperses stubborn food stagnation via emesis when other methods are insufficient

Clinical Applications in TCM

• Wind-phlegm epilepsy or sudden loss of consciousness with rattling throat — combined with Bai Fan (Alumen) in powder form for forced emesis
• Phlegm-heat lodged in the throat with difficulty swallowing — small dose decoction or topical throat application
• Scabies, tinea capitis, or head lice — topical paste with sesame oil or vinegar
• Chronic phlegm nodules unresponsive to standard treatment — combined with Gua Di (Pedicellus Cucumeris) for strong emetic action
• Snuff preparation for blocked nasal passages due to thick phlegm — minimal quantity insufflated

Precautions & Safety

• Dosage: 0.3–0.6 g in pill or powder form; 1–3 g maximum for topical decoction — never exceed; internal use requires specialist supervision
• Contraindicated in pregnancy, qi or blood deficiency, and all weak/debilitated patients
• Incompatible (十八反, Eighteen Incompatibilities) with all Ren Shen (Ginseng), Sha Shen, Dan Shen, Ku Shen, Xi Xin, and Bai Shao — strict classical prohibition
• External use only on intact skin; avoid mucous membranes and open wounds
• Toxic alkaloids (jervine, veratramine) can cause severe bradycardia, hypotension, and respiratory depression in overdose

Classical TCM Formulas

• Li Lu San (藜芦散): historical topical formula for scabies — EXTREMELY DANGEROUS internally.
• Li Lu is of primarily historical/toxicological interest. Modern emetics (ipecac) and safer dermatological agents have replaced all its indications.
• Veratrum alkaloids have been investigated as antihypertensives but rejected due to unacceptable toxicity.

Herb Combinations

• Li Lu (藜芦) + Gua Di (瓜蒂): the extreme emetic combination for Phlegm obstruction — historically used to induce vomiting in Phlegm-stroke airway emergencies.
• Li Lu (藜芦) TOPICAL use (historical): diluted tincture for scabies and parasitic skin conditions.
• MODERN WARNING: Li Lu is EXTREMELY DANGEROUS — NOT for internal use. Safer alternatives exist for all historical indications.
• Contraindicated with Ren Shen, Sha Shen, Dan Shen, Xuan Shen, Xi Xin, and Bai Shao (十八反).

Pharmacology & Research

Alkaloids (jervine, cyclopamine, veratramine): emetic, hypotensive, and antitumour activity in experimental models.
Steroidal compounds: inhibit ion channels, accounting for cardiovascular and neuromuscular toxicity.
Antiparasitic constituents: demonstrate activity against ectoparasites (lice, mites) in topical preparations.

Classical Descriptions

• “Li Lu induces vomiting of wind-phlegm and kills the three worms; it governs the hundred maladies of evil qi and malign wind.” — *Shennong Bencao Jing* (神农本草经), lower-grade herb classification