About This Herb*
Traditional Chinese Medicine background and properties
Herb Description*
Di Long (earthworm) is a classic animal-derived medicine used in Chinese medicine to address conditions involving blocked circulation, high fevers with seizures, wheezing from lung heat, and swelling with reduced urination. It is best known for its ability to open the body's network vessels, making it a key ingredient in formulas for stroke recovery and joint pain. Despite its unusual origin, it has a long history of safe use spanning over two thousand years.
Herb Category*
Main Actions*
- Settles Fright and Calms Convulsions
- Calms the Liver and Extinguishes Wind
- Unblocks the Channels and Collaterals
- Calms Wheezing
- Promotes Urination
How These Actions Work*
'Clears Heat and arrests convulsions' means Di Long can bring down high fevers and stop seizures or spasms triggered by excessive Heat. Its cold, salty nature makes it especially suited for acute febrile illnesses where Heat has stirred up internal Wind, causing delirium, convulsions, or loss of consciousness. This is one of its most classical uses, recorded since the Shen Nong Ben Cao Jing.
'Extinguishes Wind and calms the Liver' refers to Di Long's ability to settle internal Wind patterns associated with the Liver, such as headaches, dizziness, or tremors caused by Liver Yang rising. Its salty taste softens and descends, helping to anchor rising Yang and settle agitated movement in the body.
'Unblocks the channels and collaterals' is Di Long's most widely used action in modern practice. As an animal substance, Di Long has a penetrating, burrowing nature that allows it to reach deep into the body's network vessels (collaterals). This makes it highly valued for conditions where blockage in the channels causes paralysis, numbness, joint pain, or restricted movement, such as post-stroke hemiplegia or chronic joint pain (Bi syndrome).
'Calms wheezing' means Di Long can relax the airways and ease breathing difficulty. This applies specifically to wheezing and asthma caused by Lung Heat. Its cold nature clears Heat from the Lungs while its channel-opening properties help relieve bronchial constriction. The active compound succinic acid is considered the main component responsible for this effect.
'Promotes urination' means Di Long can help the body expel excess fluid through the urinary system. This is used in cases of edema with scanty urine, particularly when Heat is involved. It enters the Urinary Bladder channel, directly supporting this function.
Patterns Addressed*
In TCM, symptoms cluster into recognizable patterns of disharmony that reveal what's out of balance in the body. Di Long is traditionally associated with these specific patterns.
The following describes this herb's classification within Traditional Chinese Medicine theory and is provided for educational purposes only.
Why Di Long addresses this pattern
Di Long's cold, salty nature and its strong affinity for the Liver channel make it well suited for Wind-Stroke affecting the channels and collaterals. In this pattern, Wind (often combined with Blood stasis or Qi deficiency) obstructs the network vessels, leading to hemiplegia, numbness, and impaired speech. Di Long's outstanding ability to penetrate and unblock the collaterals directly addresses this obstruction. Its burrowing, mobile nature (described classically as 'good at crawling through passages') enables it to guide other medicines through the entire body's network vessels, restoring circulation to paralyzed limbs. This is the action showcased in Bǔ Yáng Huán Wǔ Tāng.
A practitioner would look for one or more of these signs
One-sided paralysis after stroke
Numbness or tingling in the extremities
Difficulty speaking clearly
Deviation of mouth and eye
Why Di Long addresses this pattern
When extreme Heat generates internal Wind, it can cause high fever, delirium, convulsions, and loss of consciousness. Di Long's cold nature directly clears this Heat, while its salty taste descends and anchors the rising movement of Liver Wind. It enters the Liver channel, the organ most closely linked to internal Wind in TCM theory. By simultaneously clearing Heat and extinguishing Wind, Di Long calms the spasms and convulsions that characterize this dangerous pattern. This dual action makes it particularly effective for febrile convulsions in both children and adults.
A practitioner would look for one or more of these signs
Persistent high fever
Seizures or convulsions triggered by fever
Confused or agitated mental state
Why Di Long addresses this pattern
In Bi syndrome (painful obstruction) caused by Wind, Dampness, and Heat lodging in the joints and channels, Di Long's cold nature helps clear the Heat component while its channel-unblocking action directly addresses the obstruction. Its Liver channel entry is relevant because the Liver governs the sinews. By penetrating deep into the collaterals and clearing Heat, Di Long relieves the swollen, painful, hot joints characteristic of this pattern. It is often paired with other Wind-Damp resolving and Blood-moving herbs for chronic joint conditions.
A practitioner would look for one or more of these signs
Red, swollen, painful joints
Pain in multiple joints with reduced mobility
Limb numbness and heaviness
Why Di Long addresses this pattern
When Heat accumulates in the Lungs, it can cause wheezing, coughing, and difficulty breathing. Di Long's cold nature clears Lung Heat, while its channel-opening properties help relax constricted airways. It enters the Lung channel and contains succinic acid, which modern research confirms can relax bronchial smooth muscle. This makes Di Long valuable for asthma and wheezing specifically associated with Heat, not Cold-type wheezing. It addresses both the root (Heat) and the symptom (bronchospasm).
A practitioner would look for one or more of these signs
Wheezing and labored breathing from Lung Heat
Cough with thick yellow phlegm
TCM Properties*
Cold
Salty (咸 xián)
Animal — whole (全虫 quán chóng)
This is partial information on the herb's TCM properties. More detailed information is available on the herb's dedicated page
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.