Wu Zhu Yu
StarTetradium ruticarpum (A.Juss.) Hartley
Synonyms: Euodia ruticarpa, Euodia officinalis, Cyclocarpus japonicus, Euodia rugosa, Ampacus ruticarpa, Euodia ruticarpa var. officinalis, Euodia ruticarpa var. bodinieri, Euodia compacta var. meionocarpa, Euodia ruticarpa f. meionocarpa, Boymia ruticarpa, Euodia compacta, Euodia hirsutifolia, Euodia bodinieri
Traditionally used for
- Headaches
- Digestion
- Bowel health
- Pain & joints
- Blood pressure
Cautions & contraindications
- Pregnancy
- Toxic — professional use only
☯ TCM Properties
Dispels Cold and Alleviates Pain; Directs Rebellious Qi Downward and Stops Vomiting; Assists Yang and stops diarrhea; Warms the Middle and Dries Dampness; Soothes the Liver and Regulates Qi
Traditional Chinese Uses
Wu Zhu Yu (evodia fruit) is a warm, toxic herb that warms the Liver and Stomach, disperses cold, descends rebellious Qi, and stops pain. It is the primary herb for the classical Liver-Stomach cold pattern presenting with vertex headache, flank pain, acid regurgitation, vomiting, and cold abdominal pain. It is also used topically for foot soaking in patients with hypertension where ascending Liver Fire needs to be drawn downward. Its warm, stimulating nature requires careful dosing, as it is toxic in excess.
Western Herbalism Properties
Used In Formulas (12)
Relationships
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Botanical Description
Tetradium ruticarpum (A.Juss.) T.G.Hartley (Rutaceae), formerly Evodia rutaecarpa, is a small dioecious deciduous tree 2.5-8 m tall native to China, with pinnately compound aromatic leaves of 5-11 ovate to elliptic leaflets dotted with translucent oil glands, and dense terminal corymbose panicles of small greenish-white flowers. The unripe to just-ripe fruits are five-lobed schizocarpic capsules 2-5 mm across, reddish-brown to purplish, that split into follicles containing shiny black seeds. For Wu Zhu Yu, fruits are harvested in August-October before fully ripening, sun-dried, and processed (often with licorice decoction) to reduce acrid intensity. In TCM, Wu Zhu Yu is acrid and bitter in flavor, hot in nature, and slightly toxic, entering the Liver, Spleen, Stomach, and Kidney channels; it warms the middle, dispels cold, descends rebellious qi, and stops pain and vomiting.
Active Constituents
Evodiamine
Indoloquinazoline (quinazolinocarboline) alkaloidConcentration: Major indole alkaloid of the fruit
A principal bioactive alkaloid with analgesic, anti-inflammatory, thermogenic (TRPV1 agonist), anti-obesity and antitumor activity in experimental models; contributes to the warming and pain-relieving actions of the herb.
Rutaecarpine
Indoloquinazoline (quinazolinocarboline) alkaloidConcentration: Major indole alkaloid of the fruit
Vasodilatory, anti-inflammatory and gastroprotective alkaloid. It is a potent modulator of cytochrome P450 1A2 (inhibition of the enzyme in vitro but induction on repeated dosing), the basis of important herb-drug interactions.
Dehydroevodiamine
Quinazolinocarboline alkaloidConcentration: Minor-to-moderate alkaloid
Shows cardiovascular (antiarrhythmic, hypotensive) and neuroprotective activity, including acetylcholinesterase inhibition in experimental studies.
Evodin / limonin (limonoids)
Limonoid (triterpenoid)Concentration: Bitter principle of the fruit
Bitter limonoids contributing to the characteristic taste and to anti-inflammatory and digestive effects.
Evocarpine
Quinolone alkaloidConcentration: Minor alkaloid
A quinolone alkaloid with antimicrobial activity, including reported activity against Helicobacter pylori and other bacteria.
Evodol / synephrine and volatile oil components
Mixed (protoalkaloid / essential oil)Concentration: Minor constituents of the essential oil fraction
The volatile oil (including evodene and ocimene-type terpenes) contributes the aromatic, warming, qi-descending quality used to stop vomiting and dispel cold.
⚠ Drug Interactions
Theophylline
In rats, pretreatment with Evodia rutaecarpa extract and the formula Wu-Chu-Yu-Tang significantly and dose-dependently decreased theophylline blood levels, attributed to induction of CYP1A2/CYP2E1-mediated theophylline metabolism.
Clinical note: Given theophylline's narrow therapeutic index, avoid concurrent use or monitor theophylline levels closely.
Caffeine
Rutaecarpine induces CYP1A2 (and CYP2E1) on repeated dosing, accelerating the metabolism of caffeine and shortening its half-life in animal studies.
Clinical note: May reduce caffeine effect; relevant for other CYP1A2 substrates as well.
CYP1A2 substrate drugs (e.g., clozapine, olanzapine, tizanidine, duloxetine)
Because rutaecarpine both inhibits CYP1A2 acutely and induces it with repeated exposure, plasma levels of narrow-index CYP1A2 substrates could rise or fall depending on timing and duration of use.
Clinical note: Use caution and monitor for altered efficacy or toxicity of CYP1A2-metabolized drugs.
Dosage
| Form | Amount | Frequency | Duration | Population | Notes |
|---|---|---|---|---|---|
| decoction | 2–5 g | Daily | — | — | 中国药典 2020 【用法与用量】2～5g。外用适量。 【性味与归经】辛、苦，热；有小毒。归肝、脾、胃、肾经。 — Chinese Pharmacopoeia 2020, quoted verbatim; route and cautions preserved. Replaces a cleared category-filler value. |
Preparation Methods
Decoction (Tang), often processed
Parts: unripe fruit
Typical dose 1.5-4.5 g of the dried near-ripe fruit. It is toxic and harsh when raw, so it is usually processed (e.g., stir-fried, or soaked/boiled with licorice water) to reduce toxicity before decocting. Doses are kept low.
Prepared / stir-fried (paozhi)
Parts: fruit
Dry-fried or processed with licorice decoction to moderate its hot, drying and mildly toxic nature; used in formulas such as Wu Zhu Yu Tang for cold-type headache, vomiting and abdominal pain.
Dui Yao — Herb Pairs
The classical two-herb combinations this herb appears in, each with an action neither herb has alone.
Together the bitter cold and the acrid warm drain Liver fire, direct rebellious Stomach qi downward and stop acid regurgitation and vomiting.
Classic indication: hypochondriac pain with acid reflux and bitter taste from Liver fire attacking the Stomach.
Core pair of a classical formula — Zuo Jin Wan, Dan Xi Xin Fa (Zhu Danxi)
Warming the Liver and stomach and directing rebellious qi downward, combined with warming the stomach to stop vomiting, which together settle cold rising turbid yin.
Cold in the Liver and stomach with vomiting of clear fluid, vertex headache, or dry heaves with frothy saliva.
Core pair of a classical formula — Wu Zhu Yu Tang, Shang Han Lun (Zhang Zhongjing)
Warming the Spleen and Kidney while astringing the intestines, the pair treats chronic daybreak diarrhea from cold that neither checks as well alone.
Also contained in Si Shen Wan.
Core pair of a classical formula — Wu Wei Zi San, Pu Ji Ben Shi Fang (Xu Shuwei)
Evidence Tier
Limited evidence · 2 studiesRecorded studies by study design, strongest design at the top. This is a study-design tier only, not a GRADE rating: it does not weigh risk of bias, consistency or precision.
Systematic review / meta-analysis
0
Randomized controlled trial
0
Other clinical trial
0
Observational / case report
0
In vitro / animal
2
2 verified · 0 unverified
Other / unclassified
0
Verified: design read from PubMed for a DOI that resolves to the cited paper Unverified: taken from the study's recorded description
Clinical Studies
Herb-drug interaction of Evodia rutaecarpa extract on the pharmacokinetics of theophylline in rats
Three-day pretreatment of rats with Evodia rutaecarpa ethanol extract or Wu-Chu-Yu-Tang significantly and dose-dependently lowered intravenous theophylline blood levels measured by microdialysis-HPLC, indicating a herb-drug interaction via induction of theophylline metabolism.
Alteration of the pharmacokinetics of theophylline by rutaecarpine, an alkaloid of the medicinal herb Evodia rutaecarpa, in rats
Rutaecarpine, an alkaloid of Evodia rutaecarpa, altered theophylline pharmacokinetics in rats consistent with induction of CYP1A-mediated metabolism, supporting a mechanistic basis for evodia-theophylline interactions.
⚠ Safety & Contraindications
- Pregnancy
- Toxic — professional use only
Contraindications
Use with caution in pregnancy and in yin deficiency with heat.
Safety Warnings
- Not for prolonged use or in large doses.
- Rutaecarpine induces CYP1A2 and can lower the levels of drugs cleared by it — including theophylline and caffeine.
⚠ Toxicity Information
Dry mouth, dizziness, abdominal discomfort and visual disturbance at higher doses; hepatotoxicity is reported on prolonged use.
Historical Texts
Shen Nong Ben Cao Jing (Divine Farmer's Materia Medica)
c. 200 CE, Han DynastyShang Han Lun (Treatise on Cold Damage), Zhang Zhongjing
c. 220 CE, Han DynastyReferences
- Jan WC, Lin LC, Chen CF, Tsai TH. Herb-drug interaction of Evodia rutaecarpa extract on the pharmacokinetics of theophylline in rats . Journal of Ethnopharmacology (2005) [DOI]
- Tan Q, Zhang J. Evodiamine and Its Role in Chronic Diseases . Advances in Experimental Medicine and Biology (2016) [DOI]
- Bensky D, Clavey S, Stoger E. Chinese Herbal Medicine: Materia Medica, 3rd Edition (Wu Zhu Yu) . Eastland Press (2004) [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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