Wu Ling Zhi (五灵脂) — Flying Squirrel Feces: TCM Uses & Shi Xiao San

At a Glance

Herb: Wu Ling Zhi
Chinese name: 五灵脂 (Wǔ Líng Zhī)
Latin name: Trogopterus xanthipes feces
Nature: Warm
Taste: Bitter / Sweet
Meridian: Liver / Spleen
Category: Herbs that Invigorate Blood and Resolve Stasis
Introduction: Wu Ling Zhi (五灵脂), the dried feces of Trogopterus xanthipes Milne-Edwards (Eurasian flying squirrel), is an animal-derived herb with a history in the Chinese materia medica since the Song dynasty. Despite its unusual origin, it is one of the most effective herbs for dispelling blood stasis and relieving acute pain — particularly epigastric and menstrual pain — and forms one of the most famous two-herb pairs in TCM with Pu Huang (Shi Xiao San). Modern pharmacology has identified uric acid derivatives, resin acids, and flavonoids with analgesic, antispasmodic, anti-platelet, and coagulation-regulating activities.

Activates blood and dispels blood stasis — particularly effective for acute stabbing pain
Relieves pain — one of the strongest herbs for epigastric and menstrual pain from blood stasis
Stops bleeding (charred form, 炒五灵脂) — arrests uterine bleeding from blood stasis
Resolves toxicity — topical use for snake and insect bites

Epigastric and abdominal pain from blood stasis: fixed, stabbing, worse with pressure
Dysmenorrhea and postpartum abdominal pain from blood stasis
Chest pain (angina) from blood stasis in the heart
Uterine bleeding with clots from blood stasis — use charred (炒五灵脂)
Topical: snake bites and toxic insect stings — powder applied to wound

Standard dose: 3–10 g; wrap in cloth when decocting (包煎) to prevent cloudiness
Incompatible with Ren Shen — one of the Nineteen Incompatibilities (十九畏); do not combine
Contraindicated in pregnancy — strong blood-activating action may cause miscarriage
Use with caution in blood deficiency without stasis
The strong smell may be reduced by stir-frying with vinegar (醋炒五灵脂)

Shi Xiao San (失笑散): Wu Ling Zhi + Pu Huang in equal parts — the classic formula name means ‘powder that causes unexpected laughter’ (pain resolves so suddenly); activates blood, dispels stasis, and relieves pain; for epigastric pain, dysmenorrhea, and postpartum pain
Shao Fu Zhu Yu Tang (少腹逐瘀汤): Wu Ling Zhi, Pu Huang, Xiao Hui Xiang, Yan Hu Suo, Mo Yao, Dang Gui, Chuan Xiong, Chi Shao, Gan Jiang, Rou Gui — for lower abdominal blood stasis with cold

蒲黄 (Pú Huáng) — classic pair (失笑散 Shī Xiào Sǎn): blood stasis causing epigastric, abdominal, or postpartum pain; dysmenorrhea; lochia retention. 2. 没药 (Mò Yào) + 乳香 (Rǔ Xiāng) — traumatic injuries with stasis. 3. 延胡索 (Yán Hú Suǒ) — strong analgesic combination for chest and abdominal stasis pain. 4. 川芎 (Chuān Xiōng) + 当归 (Dāng Guī) — amenorrhea and dysmenorrhea from blood stasis. Source: 太平惠民和剂局方 (失笑散), 本草纲目.

Analgesic
- blocks central and peripheral pain receptors
- especially effective for visceral pain
Anticoagulant
- inhibits ADP-induced platelet aggregation
- prolongs bleeding and clotting time
Antispasmodic
- relaxes smooth muscle of uterus and intestines
Anti-inflammatory
- reduces prostaglandin E₂ and thromboxane B₂ production
Incompatibility
- antagonizes Rén Shēn (人参) — avoid concurrent use (十八反 / eighteen incompatibilities list)

Ben Cao Gang Mu (《本草纲目》): ‘Flying Squirrel Feces is an herb of the Foot Jue Yin Liv er channel; both flavor and qi are thick — yin within yin — hence it enters the blood aspect; use raw to move blood, stir-fry to stop bleeding.’
Kai Bao Ben Cao (《开宝本草》): ‘Governs Heart and abdominal cold qi, childhood five-gan malnutrition, wards off pestilence, treats intestinal wind, promotes free flow of qi and blood vessels, and female amenorrhea.’
Ben Cao Jing Shu (《本草经疏》): ‘A key herb for moving blood, specializing in dispersing all blood-qi pain in the Heart and abdomen.’