Ingredient Fungus / Mushroom (菌类 jūn lèi)

Lei Wan

Omphalia · 雷丸

Omphalia lapidescens Schroet. · Omphalia

Also known as: Zhu Ling (竹苓), Lei Shi (雷实), Zhu Ling Zhi (竹铃芝)

Lei Wan is a fungus that has been used for centuries to expel intestinal parasites, especially tapeworms. It is taken as a powder to break down the worms so they can be eliminated from the body. It is also applied externally to reduce excessive sweating.

Category Parasite-expelling herbs (驱虫药)
Therapeutic focus Digestive health Parasite infections Skin health Children's health

TCM Properties

Temperature

Cold

Taste

Bitter (苦 kǔ)

Channels entered

Stomach, Large Intestine

Parts used

Fungus / Mushroom (菌类 jūn lèi)

Educational content • Consult qualified TCM practitioners for diagnosis and treatment

What This Ingredient Does

Every ingredient has a specific set of actions — here's what Lei Wan does in the body, explained in both everyday and TCM terms

Therapeutic focus

In practical terms, Lei Wan is primarily used to support these areas of health:

Digestive health Parasite infections Skin health Children's health

TCM Actions

In TCM terminology, these are the specific therapeutic actions that Lei Wan performs to restore balance in the body:

Kills parasites Dispels accumulation Reduces masses

How these actions work

'Kills parasites' means Lei Wan directly destroys intestinal worms, especially tapeworms, by breaking down their protein structure with a unique enzyme. 'Dispels accumulation' refers to its ability to clear the abdominal masses and food stagnation caused by parasites. 'Reduces masses' indicates its traditional and modern use for tumors and growths, where it helps dissolve abnormal tissue.

Patterns Addressed

In TCM, symptoms cluster into recognizable patterns of disharmony. Lei Wan is used to help correct these specific patterns.

Why Lei Wan addresses this pattern

Lei Wan directly kills intestinal parasites, and its cold, bitter nature clears the heat and dampness that often accompany parasitic infections. Its specific proteolytic enzyme dissolves the protein structure of worms, making it highly effective against tapeworms, hookworms, and roundworms.

A practitioner would look for one or more of these signs

Abdominal Pain
Anal Itching
Weight Loss
Diarrhea

Commonly Used For

These are conditions where Lei Wan is frequently used — but only when they arise from the specific patterns it addresses, not in all cases

Arises from: Intestinal Parasite

TCM Interpretation

TCM views tapeworm infection as an invasion of intestinal parasites that disrupts the Spleen and Stomach's transformation and transportation functions, leading to dampness, heat, and Qi stagnation. The worm's presence consumes Qi and Blood, causing malnutrition and abdominal pain.

Why Lei Wan Helps

Lei Wan contains a unique proteolytic enzyme that dissolves the protein structure of tapeworm bodies, causing them to detach from the intestinal wall and be expelled. Its cold, bitter nature also clears the damp-heat that often accompanies such infections.

Also commonly used for

Hyperhidrosis

Applied externally as powder to reduce excessive sweating

Ingredient Properties

Every ingredient has an inherent temperature, taste, and affinity for specific channels — these properties determine how it interacts with the body

Temperature

Cold

Taste

Bitter (苦 kǔ)

Channels Entered

Stomach Large Intestine

Parts Used

Fungus / Mushroom (菌类 jūn lèi)

Dosage & Preparation

These are general dosage guidelines for Lei Wan — always follow your practitioner's recommendation, as dosages vary based on the formula and your individual condition

Standard dosage

15–21g per day, taken as powder in divided doses of 5–7g each, after meals, for a course of 3 days. Not to be decocted.

Maximum dosage

21g per day in divided doses. Exceeding this dose may cause nausea, vomiting, abdominal discomfort, and dizziness. Do not extend the course beyond 3 days without re-evaluation.

Dosage notes

Lei Wan must always be taken as a raw powder at room or slightly warm temperature; never boil or decoct it. The active proteolytic enzyme denatures above approximately 60°C, rendering the herb ineffective. For tapeworm infections, a typical regimen is 5–7g of powder taken with warm water three times daily on an empty or slightly filled stomach for 3 consecutive days. Combining with Bing Lang (Areca nut) enhances efficacy.

Preparation

Never decoct. The herb must be dry-ground to a fine powder and administered as is. Mix the powder with lukewarm water (not hot) immediately before ingestion. For children, the powder can be mixed into a small amount of congee or soft food. Store the powder in a cool, dry place away from heat.

Processing Methods

In TCM, the same ingredient can be prepared in different ways to change its effects — here's how processing alters what Lei Wan does

Processing method

Clean the dried sclerotia, remove soil and impurities, then crush to a fine powder. No heat, steaming, or baking is used at any stage.

How it changes properties

Preserves the heat-sensitive proteolytic enzyme, which is essential for the herb's anti-parasitic action. Any form of heating would irreversibly denature this enzyme and render the herb ineffective.

When to use this form

For all internal use. This is the only clinically effective form; all traditional preparations that involve heating are now obsolete.

Common Ingredient Pairs

These ingredients are traditionally combined with Lei Wan for enhanced therapeutic effect

Bing Lang
Bing Lang 1:1 (e.g., Lei Wan 6g : Bing Lang 6g)

Bing Lang paralyzes and expels the worm body, while Lei Wan dissolves the worm's protein structure, ensuring complete elimination. Together they provide a powerful synergistic anti-parasitic action.

When to use: For all types of intestinal parasites, especially tapeworms, with abdominal pain and accumulation.

Da Huang
Da Huang Lei Wan 6g : Da Huang 3-9g

Da Huang purges the intestines and drains damp-heat, clearing the toxic accumulation left by parasites, while Lei Wan directly kills the worms. This pair addresses both the cause and the symptoms.

When to use: When parasitic infection is accompanied by constipation and damp-heat signs such as foul-smelling stools.

Mu Xiang
Mu Xiang Lei Wan 6g : Mu Xiang 3-6g

Mu Xiang regulates Qi and alleviates abdominal pain caused by parasitic accumulation, complementing Lei Wan's anti-parasitic action. It also promotes the movement of Qi to help expel the worms.

When to use: For parasitic infections with significant abdominal distension and pain.

Comparable Ingredients

These ingredients have overlapping uses — here's how to tell them apart

Shi Jun Zi
Lei Wan vs Shi Jun Zi

Both expel parasites, but Shi Jun Zi is sweet and warm, primarily used for roundworms and pinworms with Spleen Qi Deficiency, while Lei Wan is cold and bitter, better for tapeworms and conditions with heat signs.

Bing Lang
Lei Wan vs Bing Lang

Bing Lang is warm and acrid, drives Qi and expels parasites, effective for multiple intestinal parasites and also promotes Qi movement; Lei Wan is cold and specifically dissolves the protein structure of parasites, making it stronger for tapeworms but without the Qi-moving effect.

Identity & Adulterants

Related species and common adulterations to be aware of when sourcing Lei Wan

Lei Wan is sometimes confused with other fungal sclerotia of similar appearance. Inferior products may be from related but ineffective species. The most critical quality issue is overheating during processing: heat destroys the proteolytic enzyme, rendering the herb useless. Adulterated material may have a polished, waxy appearance, be brittle, and lack the characteristic bitter taste and marble-like interior. Authentic Lei Wan must always be confirmed by trained personnel.

Educational content — always consult a qualified healthcare provider or TCM practitioner before using any ingredient.

Toxicity Classification

Classical Chinese pharmacopoeia toxicity rating for Lei Wan

Non-toxic

Lei Wan is classified as non-toxic by the modern Chinese Pharmacopoeia, though some classical texts note 'slight toxicity.' Its active proteolytic enzyme is destroyed by heat, so raw powder use at the recommended dosage does not produce systemic toxicity. Overdose may cause gastrointestinal irritation, nausea, or dizziness. Avoid long-term use.

Contraindications

Situations where Lei Wan should not be used or requires extra caution

Caution

Pregnancy — classical texts state 'li bu li nv zi' (benefits men, not women), and long-term use can cause impotence; use with caution during pregnancy.

Caution

Postpartum and during menstruation — the cold nature may slow recovery; use only when parasites are present and under guidance.

Caution

Spleen-Stomach cold deficiency without parasitic infestation — the bitter cold nature can injure the middle burner if no worms are present.

Caution

Long-term use — classical texts warn that prolonged administration can lead to yin wei (impotence) and general debility; limit to short courses.

Classical Incompatibilities

Traditional Chinese pharmacological incompatibilities — herbs or substances to avoid combining with Lei Wan

Classical texts note that Lei Wan should avoid combination with Bì Xù (Polygonum aviculare, 蓄根) and Gé Gēn (Pueraria lobata, 葛根). This is a traditional incompatibility, not part of the standard 十八反 or 十九畏 lists.

Special Populations

Important considerations for pregnancy, breastfeeding, and pediatric use

Pregnancy

Generally contraindicated during pregnancy. Although no modern teratogenicity studies have been published, classical texts state that the herb 'li nan bu li nv zi' (benefits men, not women) and that prolonged use causes impotence. The herb's cold, descending action and anti-parasitic effect could potentially disturb the uterus. Use only when clearly needed and under the supervision of a qualified practitioner.

Breastfeeding

No specific data are available on the excretion of Lei Wan components in breast milk. Due to the limited safety information and the potential for gastrointestinal disturbance in the infant, use during breastfeeding should be avoided or undertaken only under strict medical supervision.

Children

Dosage for children should be reduced in proportion to body weight. For infants and young children, crush the powder very finely and mix with a little warm water; use only under close medical supervision. The course is limited to 3 days; do not use for longer periods.

Drug Interactions

If you are taking pharmaceutical medications, be aware of these potential interactions with Lei Wan

No well-documented interactions with pharmaceutical drugs have been reported. The proteolytic enzyme might theoretically affect the absorption of protein-based drugs, but this has not been clinically observed. As a precaution, separate administration from other oral medications by at least 2 hours.

Dietary Advice

Foods and dietary considerations when taking Lei Wan

Avoid greasy, fried, or overly sweet foods during treatment, as these can weaken the Spleen and promote a damp environment that favors parasites. Do not take the powder with hot water, tea, or acidic liquids that could denature the enzyme. Light, easily digestible meals are recommended.

Botanical Description

Physical characteristics and morphology of the Lei Wan source organism

Lei Wan is the dried sclerotium of the fungus Omphalia lapidescens Schroet., which grows underground, often in association with decaying bamboo roots. It has no stems, leaves, or flowers. The sclerotium is roughly spherical or irregularly shaped, 1–3 cm in diameter, with a blackish-brown surface marked by a network of fine raised ridges. The interior is white to pale yellowish-white, with a marble-like texture. It is odorless and tastes slightly bitter with a gritty consistency.

Sourcing & Harvesting

Where Lei Wan is sourced, when it's harvested or collected, and how to assess quality

Harvesting season

Autumn, when the sclerotium is fully mature. It can occasionally be collected in spring and winter, but autumn harvest yields the highest quality.

Primary growing regions

Mainly produced in Gansu, Sichuan, Yunnan, and Guizhou provinces. The sclerotia found under bamboo groves in these regions are considered the best quality.

Quality indicators

Good quality Lei Wan sclerotia are hard, solid, and heavy, with a blackish-brown surface showing fine raised net-like ridges. The cross-section should be white or pale yellowish-white with distinct marble-like markings, and have a faintly bitter taste with a gritty, slightly sticky texture on chewing. Avoid specimens that are hollow, soft, have a dark or keratinized (horny) cross-section, or show signs of mold — these indicate poor quality or incorrect processing that destroys the active enzyme.

Classical Texts

Key passages from the classical Chinese medical texts that describe Lei Wan and its therapeutic uses

《神农本草经》 (Shen Nong Ben Cao Jing):
主杀三虫，逐毒气。
"Kills the three worms, expels toxic qi."

《本草纲目》 (Ben Cao Gang Mu), Li Shizhen:
皆霹雳击物精气所化。此物生土中，无苗叶而杀虫逐邪，犹雷之丸也。竹之余气所结，故曰竹苓。
"All are transformed from the essence of thunder striking things. This substance grows in the soil, has no leaves yet kills worms and expels evil, like a thunder pill. It is formed from the residual qi of bamboo, hence called Zhu Ling."

《名医别录》 (Ming Yi Bie Lu):
作摩膏，除小儿百病，逐邪气恶风汗出，除皮中热结积蛊毒，白虫寸白自出不止。久服，令人阴痿。
"Made into a medicated plaster, it eliminates a hundred diseases of children, drives out evil qi and abnormal sweating from wind, removes heat accumulation and gu poison in the skin, and causes white worms to come out unceasingly. Prolonged use makes men impotent."

Historical Context

The history and evolution of Lei Wan's use in Chinese medicine over the centuries

The name Lei Wan (雷丸) literally means "thunder pill," reflecting the belief that it was formed from the essence of thunderbolts. Li Shizhen explained its alternative name Zhu Ling (竹苓) as deriving from the residual qi of bamboo. A famous story from the Song dynasty book Xu Mo Ke Hui Xi tells of a man who had a "responding worm" in his abdomen that mimicked his words; he was cured after reading the Shen Nong Ben Cao Jing aloud and taking the herb whose name stopped the echo — which was Lei Wan. This tale illustrates the ancient recognition of its potent anti-parasitic effect. First recorded in the Shen Nong Ben Cao Jing, Lei Wan has been consistently used through history as a primary agent for expelling intestinal worms, especially tapeworms. Modern research has identified a heat-sensitive proteolytic enzyme as its active component, explaining why it must be taken as a raw powder and never decocted.