About This Herb*
Traditional Chinese Medicine background and properties
Herb Description*
Catechu is a dried extract from the Acacia catechu tree, used primarily for healing stubborn wounds, stopping bleeding, and drying weeping skin conditions. It is applied externally as a powder for sores, ulcers, eczema, and mouth sores, and taken internally in small doses for bleeding or coughs with yellow phlegm. Despite its name, it is not a tea but a concentrated herbal paste with strong astringent and wound-healing properties.
Herb Category*
Main Actions*
- Stops bleeding and promotes tissue regeneration
- Absorbs Dampness and Heals Sores
- Invigorates Blood and Alleviates Pain
- Clears Lung Heat and Transforms Phlegm
How These Actions Work*
'Stops bleeding and promotes tissue regeneration' means Er Cha can both halt bleeding and encourage the growth of new tissue over wounds. Its astringent taste gives it a natural ability to constrict and bind, which helps control bleeding from cuts, trauma, or internal hemorrhage. It is used both internally (for vomiting blood, nosebleeds, blood in the stool or urine) and applied directly to wounds as a powder.
'Absorbs dampness and closes sores' refers to its ability to dry out weeping, oozing skin lesions and promote their healing. This is the action Er Cha is most famous for. When sores, ulcers, or eczema patches are slow to heal and continue to seep fluid, Er Cha's astringent and slightly cooling nature helps dry the area, reduce inflammation, and encourage the skin to close over. It is commonly applied as a fine powder mixed with other herbs.
'Invigorates Blood and stops pain' means that despite being astringent, Er Cha also has a bitter taste that can move stagnant Blood and relieve pain from traumatic injuries. This is why it appears in famous trauma formulas. It enters the Heart channel, which governs Blood circulation, allowing it to disperse bruising and blood stasis from falls and blows.
'Clears Heat from the Lungs and resolves Phlegm' refers to its cooling, bitter nature acting on the Lung channel to clear Heat and transform thick, yellow Phlegm. This action is used for coughs with yellow sputum caused by Lung Heat. It can also address mouth sores, sore throat, and other signs of upper body Heat.
Patterns Addressed*
In TCM, symptoms cluster into recognizable patterns of disharmony that reveal what's out of balance in the body. Er Cha 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 Er Cha addresses this pattern
Er Cha's cool temperature and bitter, astringent tastes directly counter Damp-Heat lodged in the skin. Its bitter taste drains Dampness and clears Heat, while its astringent quality absorbs seepage and tightens tissue. When Damp-Heat causes weeping eczema, persistent sores, or ulcers that ooze fluid and refuse to heal, Er Cha dries the dampness, cools the inflammation, and promotes the growth of new tissue. It enters the Heart and Lung channels, both of which are connected to skin health in TCM (the Lung governs the skin, the Heart governs Blood).
A practitioner would look for one or more of these signs
Weeping, oozing lesions
Chronic non-healing sores
Red, inflamed, moist skin lesions
Why Er Cha addresses this pattern
When physical injury damages the channels and Blood vessels, Blood stagnates locally, causing swelling, pain, and bruising. Er Cha enters the Heart channel and has a bitter taste that moves stagnant Blood, disperses local Blood stasis, and relieves pain. At the same time, its astringent nature stops any active bleeding from the wound, making it uniquely suited to traumatic injuries where both bleeding and bruising are present simultaneously. This is why it features prominently in trauma formulas like Qi Li San.
A practitioner would look for one or more of these signs
Swelling and bruising from impact
Traumatic cuts or lacerations with bleeding
Local pain from injury with blood stasis
Why Er Cha addresses this pattern
Er Cha is cool in nature and enters the Lung channel, enabling it to clear Heat from the Lungs. Its bitter taste descends and drains, helping to resolve thick, yellow Phlegm produced when Heat condenses Lung fluids. While it is not a primary Lung Heat herb, its ability to both clear Heat and astringe gives it a useful role in coughs where Heat and Phlegm coexist, particularly when there is also bleeding (such as coughing blood) due to Heat damaging the Lung vessels.
A practitioner would look for one or more of these signs
Cough with yellow, sticky phlegm
Coughing up blood
Mouth sores from upper body Heat
TCM Properties*
Cool
Bitter (苦 kǔ), Astringent (涩 sè)
Processed / Derived product (加工品 jiā gōng pǐn)
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.