About This Herb*
Traditional Chinese Medicine background and properties
Herb Description*
Long Kui (black nightshade) is a cooling herb used in Chinese medicine primarily for hot, inflamed conditions like boils, abscesses, skin infections, and sore throat. It also helps with difficult urination and swelling, and is widely used in China as a supportive herb alongside conventional cancer treatments. Because it contains small amounts of potentially toxic alkaloids, it should only be used under professional guidance.
Herb Category*
Main Actions*
- Clears Heat and Resolves Toxicity
- Invigorates Blood and Reduces Swelling
- Promotes Urination and Reduces Edema
- Cools the Blood and Stops Bleeding
- Dissipates Nodules and Softens Hardness
How These Actions Work*
'Clears Heat and resolves toxins' is Long Kui's primary action. Being Cold in nature and Bitter in taste, it powerfully drains Heat and eliminates toxic accumulations from the body. In practice, this means it is used for hot, inflamed conditions like boils, abscesses, sore throat, and skin infections (erysipelas, eczema). The bitter taste drives downward and dries Dampness, while the Cold nature directly opposes pathogenic Heat. This action also underlies its modern clinical use as a supportive herb in cancer treatment, where the accumulation of Heat-toxins is understood as a key factor in tumour formation.
'Invigorates Blood and reduces swelling' means Long Kui can move stagnant Blood and disperse swelling in injured or inflamed tissues. This is why classical texts such as the Ben Cao Zheng Yi describe it as "an excellent herb for surgery to clear Heat and reduce swelling" and note its use for traumatic injuries with bruising and Blood stasis. It can be applied topically as a poultice for swollen, painful injuries or sores.
'Promotes urination and reduces edema' reflects Long Kui's ability to open the water pathways through the Bladder channel. When Heat or Dampness accumulates in the lower body causing painful, scanty, or burning urination and edema, Long Kui helps by clearing the Heat and facilitating the passage of urine. This action connects directly to its use in acute kidney inflammation with swelling and reduced urine output.
'Cools Blood and stops bleeding' indicates that when Heat enters the Blood level, causing it to move recklessly and producing symptoms like vomiting blood or heavy uterine bleeding, Long Kui's Cold nature can cool the Blood and help stop the bleeding.
Patterns Addressed*
In TCM, symptoms cluster into recognizable patterns of disharmony that reveal what's out of balance in the body. Long Kui 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 Long Kui addresses this pattern
Toxic Heat is a pattern where pathogenic Heat concentrates and produces visible inflammation, often manifesting as painful red swellings, abscesses, boils, or infected sores. Long Kui is Cold in nature and Bitter in taste, giving it a strong downward-draining and Heat-clearing action. It enters the Bladder channel, which governs the body's lower waterways, but its toxin-resolving action has broad reach across skin and soft tissues. The herb directly counteracts the intense Heat and toxic accumulation at the root of this pattern, while its Blood-invigorating property helps disperse the local swelling and stagnation that accompany purulent infections.
A practitioner would look for one or more of these signs
Red, hot, painful skin abscesses
Infected sores or carbuncles with pus
Swollen, painful throat from Heat-toxins
Fiery red skin rash (erysipelas / 丹毒)
Why Long Kui addresses this pattern
When Dampness and Heat accumulate in the lower part of the body, they obstruct the Bladder's function of transforming and excreting urine. This leads to painful, burning, or scanty urination and edema. Long Kui enters the Bladder channel and is both Cold (to clear Heat) and Bitter (to drain Dampness downward). Its diuretic action opens the water passages, while its Heat-clearing property addresses the underlying inflammatory obstruction. This makes it well-suited for acute kidney inflammation or urinary tract infections presenting with this pattern.
A practitioner would look for one or more of these signs
Swelling with reduced urine output
Burning or painful urination
Urinary urgency with Heat signs
Why Long Kui addresses this pattern
When pathogenic Heat invades the Blood level, it forces Blood to move recklessly outside the vessels, causing various bleeding symptoms. Long Kui's Cold nature directly cools the Blood, while its Bitter taste helps drive the Heat downward and out. This is the basis for its classical use in treating vomiting of blood and heavy uterine bleeding (崩漏) due to Blood Heat.
A practitioner would look for one or more of these signs
Vomiting blood due to Heat in the Blood
Excessive uterine bleeding from Blood Heat
TCM Properties*
Cold
Bitter (苦 kǔ), Sweet (甘 gān)
Whole plant / Aerial parts (全草 quán cǎo)
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.