About This Herb*
Traditional Chinese Medicine background and properties
Herb Description*
Shi Wei (Pyrrosia leaf) is a fern leaf used in Chinese medicine primarily for urinary problems such as painful urination, urinary stones, and blood in the urine. It clears heat from both the Urinary Bladder and the Lungs, so it is also used for coughs and bronchitis. Additionally, it helps stop bleeding caused by excess internal heat.
Herb Category*
Main Actions*
- Promotes Urination and Relieves Stranguria
- Clears Lung Heat and Stops Cough
- Cools the Blood and Stops Bleeding
How These Actions Work*
'Promotes urination and treats painful urinary dysfunction' (利尿通淋 lì niào tōng lín) is Shi Wei's primary action. In TCM, 'lin syndrome' covers a range of urinary problems including painful, burning, or difficult urination, often with urgency or the passage of sediment. Shi Wei's bitter and sweet taste combined with its cool nature allows it to clear heat and dampness from the Urinary Bladder, restoring normal water flow. This makes it especially useful for hot, painful, bloody, or stone-type urinary complaints. Classical sources such as the Shen Nong Ben Cao Jing record that it 'treats the five types of urinary blockage and promotes the water passages.'
'Clears Lung Heat and stops coughing' (清肺止咳 qīng fèi zhǐ ké) refers to Shi Wei's ability to enter the Lung channel and cool excess heat there. When the Lungs are overheated, a person may experience coughing, wheezing, or thick phlegm. Shi Wei's cool, bitter nature descends and clears this heat, helping to calm coughs. It has been used in modern clinical practice for both acute and chronic bronchitis.
'Cools the Blood and stops bleeding' (凉血止血 liáng xuè zhǐ xuè) means Shi Wei helps control bleeding that arises from heat driving the blood recklessly out of the vessels. This includes blood in the urine, nosebleeds, coughing up blood, and heavy or prolonged menstrual bleeding. Because it both cools heat and stops bleeding, it is particularly well suited for bleeding conditions where heat is the underlying driver.
Patterns Addressed*
In TCM, symptoms cluster into recognizable patterns of disharmony that reveal what's out of balance in the body. Shi Wei 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 Shi Wei addresses this pattern
Shi Wei is one of the most characteristic herbs for Bladder Damp-Heat. Its cool, bitter nature directly clears heat and dampness from the Urinary Bladder channel, while its sweet taste gently moistens the urinary tract. By promoting urination and clearing heat simultaneously, it addresses the core pathomechanism of this pattern: damp-heat steaming in the lower burner and obstructing the Bladder's function of transforming and excreting urine. The herb restores normal urine flow and resolves the burning, painful quality caused by heat in the Bladder.
A practitioner would look for one or more of these signs
Burning, urgent, painful urination (the hallmark of hot lin syndrome)
Blood in the urine from heat damaging the Bladder vessels
Frequent, scanty urination with a feeling of incomplete emptying
Dark, concentrated urine with possible sediment
Why Shi Wei addresses this pattern
Shi Wei enters the Lung channel and its cool, bitter properties descend and clear accumulated heat from the Lungs. When Lung Heat causes coughing and wheezing, Shi Wei clears the heat and calms the Lung Qi, helping to stop coughing. Its sweet taste also gently moistens, preventing excessive drying. This makes it a supporting herb for patterns where heat congests the Lungs, producing a forceful cough or wheeze with possibly thick yellow phlegm.
A practitioner would look for one or more of these signs
Cough with thick phlegm from Lung Heat
Wheezing or labored breathing from heat congesting the Lungs
Why Shi Wei addresses this pattern
When heat enters the Blood level, it can drive blood recklessly out of the vessels, causing various types of bleeding. Shi Wei's cool nature cools the Blood, while it simultaneously has a hemostatic (bleeding-stopping) action. This dual ability to both clear the root cause (heat) and address the symptom (bleeding) makes it well suited for Blood Heat patterns that manifest as urinary bleeding, nosebleeds, or abnormal uterine bleeding.
A practitioner would look for one or more of these signs
Blood in the urine from heat forcing blood out of the vessels
Nosebleeds from blood heat rising upward
Heavy or prolonged menstrual bleeding (崩漏 bēng lòu)
TCM Properties*
Slightly Cool
Sweet (甘 gān), Bitter (苦 kǔ)
Leaf (叶 yè)
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.