Gua Lou
StarTrichosanthes kirilowii Maxim.
☯ TCM Properties
Clears Heat and Transforms Phlegm; Broadens the Chest and Dissipates Nodules; Moistens the Intestines and Unblocks the Bowels; Disperses Swelling and Dissipates Abscesses
Traditional Chinese Uses
Bai Xian Pi (densefruit pittany root bark) is a cold, bitter herb primarily used to resolve Damp-Heat skin conditions. It is a leading herb for inflammatory, weeping, itchy skin disorders including eczema, psoriasis-type conditions, and damp-type skin infections. Its ability to clear Heat toxin also extends to treating jaundice from Damp-Heat in the Liver and Gallbladder, and it appears in formulas for urinary burning and joint pain from Damp-Heat obstruction.
Western Herbalism Properties
Botanical Description
Trichosanthes kirilowii (Gua Lou, Chinese snake gourd) is a perennial dioecious climbing vine in the Cucurbitaceae family, ascending several meters by means of bifid tendrils opposite the leaves. The stems are slender, ridged, and minutely hairy. The alternate, long-petioled leaves are broadly cordate-ovate in outline, 5 to 20 centimeters across, palmately 3- to 7-lobed with coarsely toothed margins. Flowers are unisexual: staminate flowers borne in axillary racemes, pistillate flowers solitary, each with a tubular calyx and five white petals deeply fringed at the margins into a delicate lace-like fringe characteristic of the genus, opening in the evening. The fruit is an orange to orange-red globose to ovoid pepo 7 to 11 centimeters long, ripening in autumn, containing a sweetish pulp and many flattened pale brown seeds. Three distinct medicinal materials are derived: Gua Lou (whole fruit), Gua Lou Pi (peel), Gua Lou Ren (seed), and Tian Hua Fen (root). Native to China, Korea, and Japan.
Active Constituents
Triterpenoid saponins
Triterpenoid saponinConcentration: Present in pericarp and whole fruit; variable
Contribute to the expectorant, anti-inflammatory and vasodilatory actions attributed to the fruit, supporting its use for phlegm-heat cough and chest obstruction (xiong bi).
Fatty oil (trichosanic/punicic acid and other fatty acids)
Seed lipid / fatty acidsConcentration: Abundant in the seed (Gua Lou Ren), up to ~25-40% of seed
The seed oil underlies the intestine-moistening, laxative action used for constipation; conjugated fatty acids also have studied lipid-modulating properties.
Sterols (e.g., stigmasterol, beta-sitosterol)
PhytosterolConcentration: Minor constituents of fruit and seed
Plant sterols with anti-inflammatory and cholesterol-modulating activity that add to the cardiovascular and lipid effects of the fruit.
Flavonoids
FlavonoidConcentration: Minor, concentrated in the pericarp (Gua Lou Pi)
Antioxidant flavonoids of the peel are linked in network-pharmacology and experimental studies to antithrombotic and endothelium-protective effects relevant to coronary heart disease.
Amino acids and organic acids (e.g., citrulline, oxalic/malic acids)
Nitrogenous compounds / organic acidsConcentration: Water-soluble fraction of the fruit
Water-soluble constituents that contribute to the fluid-generating and mild demulcent qualities of the fruit extract.
Trichosanthin (root protein - note on plant source)
Type-1 ribosome-inactivating proteinConcentration: Concentrated in the ROOT (Tian Hua Fen), not the ripe fruit
An abortifacient, immunomodulatory and antiviral protein isolated chiefly from the Trichosanthes root, not the fruit used as Gua Lou. It is noted here to distinguish the fruit drug from the root drug and to flag the plant's overall pregnancy-related toxicity concerns.
⚠ Drug Interactions
Aconite-containing herbs (Fu Zi, Chuan Wu, Cao Wu)
Trichosanthes fruit is one of the herbs traditionally listed in the 'Eighteen Incompatibilities' (shi ba fan) as antagonistic to aconite (wu tou), so classical practice avoids combining them.
Clinical note: By convention, do not combine Gua Lou with aconite-type herbs; modern toxicological evidence is limited but the traditional prohibition is widely observed.
Antiplatelet / anticoagulant agents
Pericarp constituents show antithrombotic and anti-platelet-aggregation activity in preclinical models, so additive effects with antiplatelet or anticoagulant drugs are conceivable.
Clinical note: Monitor for bruising or bleeding if combined with aspirin, clopidogrel or warfarin; clinical significance is unconfirmed.
Dosage
| Form | Amount | Frequency | Duration | Population | Notes |
|---|---|---|---|---|---|
| decoction | 6-15g | Daily | — | — | — |
Preparation Methods
Water decoction of whole fruit (Quan Gua Lou)
Parts: ripe fruit
Typically 9-15 g of the ripe fruit decocted; used to clear phlegm-heat, widen the chest and relieve chest bi (angina-type) and phlegm cough. It is cold and moistening and is avoided in Spleen deficiency with loose stools.
Pericarp (Gua Lou Pi) decoction
Parts: fruit peel/rind
The peel is favored for clearing heat, transforming phlegm and regulating qi in the chest; often paired with Xie Bai and Ban Xia in chest-painful (xiong bi) formulas.
Seed (Gua Lou Ren) preparation
Parts: seed
Crushed seeds, about 9-15 g, are used chiefly to moisten the intestines and move the stool for dry constipation, and to transform phlegm. Classically contraindicated in pregnancy and with aconite-type herbs.
Clinical Studies
A systematic review of the effectiveness and safety of Chinese herbal medicine formula Gualou Xiebai Banxia (GLXBBX) decoction for the treatment of stable angina pectoris
Pooling 17 randomized controlled trials (1,676 patients), the Gua Lou-based GLXBBX decoction, alone or added to conventional therapy, appeared to improve angina symptoms and ECG findings versus conventional treatment alone. The authors caution that poor methodological quality and high risk of bias mean larger, double-blind trials are still needed.
Historical Texts
Jin Gui Yao Lue (Essentials from the Golden Cabinet), Zhang Zhongjing
Eastern Han, c. 220 CEBen Cao Gang Mu (Compendium of Materia Medica), Li Shizhen
Ming dynasty, 1578 CEReferences
- Chen M, Men L, Wu H, et al.. A systematic review of the effectiveness and safety of Chinese herbal medicine formula Gualou Xiebai Banxia (GLXBBX) decoction for the treatment of stable angina pectoris . Medicine (Baltimore) (2019) [DOI]
- Lu JJ, et al.. Trichosanthis Fructus: botany, traditional uses, phytochemistry and pharmacology . Journal of Ethnopharmacology (2018) [DOI]
This information is for educational purposes only and is not intended to replace professional medical advice. Always consult a qualified healthcare provider before using any herbal remedy, especially if you are pregnant, nursing, or taking medications.
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