Eupatorii Herba
Aliases：Lán Cǎo (Orchid Grass), Zé Lán (Marsh Orchid), Yuán Gěng Zé Lán (Round-Stemmed Marsh Orchid), Xiāng Shuǐ Lán (Fragrant Water Orchid), Shuǐ Xiāng (Water Fragrance), Dà Zé Lán (Large Marsh Orchid), Yàn Wěi Xiāng (Swallowtail Fragrance), Dū Liáng Xiāng (Duliang Fragrance), Zhēn Wěi Fèng (Needle-Tail Phoenix), Qiān Jīn Cǎo (Thousand Gold Herb), Shěng Tóu Cǎo (Awakening Head Herb), Hái Er Jú (Child Chrysanthemum), Nǚ Lán (Female Orchid)
Pèi Lán is a Chinese medicinal herb. It is the dried above-ground part of Eupatorium fortunei Turcz., a plant of the Asteraceae family. Pèi Lán has a fragrant aroma and a slightly bitter taste. It is considered an essential herb for aromatically resolving dampness.
Efficacy & Actions
Resolves dampness with aromatics, awakens the spleen and stimulates appetite, and releases the exterior to relieve summer heat. With its fragrant aroma, Pèi Lán enters the spleen and stomach meridians to resolve dampness and regulate the middle jiao. Its pungent and aromatic properties both resolve internal dampness and disperse external summer-heat pathogens, making it suitable for dampness obstructing the middle jiao and summer-dampness exterior syndromes.
Indications
Used for dampness obstructing the middle jiao, epigastric fullness with nausea and vomiting, sweet and greasy sensation in the mouth, halitosis, excessive salivation, summer-dampness exterior syndrome, early-stage damp-warm disease, fever with fatigue, and chest tightness with discomfort. It is also used for “Spleen-Dan” syndrome (sweet taste in the mouth, excessive salivation, halitosis) due to damp-heat in the spleen meridian.
Modern Pharmacology
Antibacterial Effects: The water decoction of Pèi Lán has inhibitory effects against Corynebacterium diphtheriae, Staphylococcus aureus, Sarcina, Proteus, and Salmonella typhi. Antiviral Effects: Pèi Lán essential oil and its components (p-cymene, neryl acetate) have direct inhibitory effects against influenza viruses. Expectorant Effects: Pèi Lán essential oil and its active monomer p-cymene have significant expectorant effects when administered orally. Anti-inflammatory and Antioxidant Effects: Compounds isolated from Pèi Lán exhibit anti-free radical and anti-inflammatory activities, and can reduce oxidative stress by activating the Nrf2 signaling pathway. Sedative and Hypnotic Effects: Pèi Lán essential oil has sedative and hypnotic properties, with main components including β-bisabolene, β-caryophyllene, and thymol tiglate. Potential Antitumor Activity: Network pharmacology analysis suggests that the main chemical components of Pèi Lán in treating type 2 diabetes include luteolin, stigmasterol, and sitosterol, involving 36 potential targets.
Ingredients
Volatile Oils: p-cymene, neryl acetate, methyl thymyl ether; also thymol, 2H-1-benzopyran-2-one, caryophyllene oxide, etc. Terpenoids: 39 thymol and acetophenone derivatives have been isolated from the aerial parts of Pèi Lán, including 8 pairs of enantiomers, 18 of which are newly reported compounds. Sterols: Taraxasterol, taraxasteryl acetate, β-amyrin palmitate, etc. Other Compounds: Luteolin, stigmasterol, sitosterol, etc.; the leaves contain coumarin, o-coumaric acid, and thymohydroquinone.
Usage & Dosage
Oral Administration: Decoction, 3–10g; fresh material may be used at 15–30g. Culinary/Tea Use: Recommended dosage of 3–6g per use. Usage Notes: Generally taken as a decoction or infusion for medicinal use; for culinary applications, it is often used as a tea or added to congee.
Contraindications
Use with caution in patients with yin deficiency and blood dryness: As the herb is aromatic and dispersing, it may consume fluids. It may aggravate symptoms in individuals with yin deficiency and blood dryness. Use with caution in patients with qi deficiency: Not suitable for those with qi deficiency and abdominal distension. Contraindicated in patients with stomach qi deficiency. Use with caution in individuals with allergies. Menstruating women should use it under the guidance of a physician.
Selected Formulas
For Spleen-Dan with Sweet Taste in the Mouth (Lan Cao Tang from Su Wen) Take Pèi Lán alone in decoction. It is used to treat sweet and greasy sensation in the mouth, excessive salivation, and halitosis caused by damp-heat in the spleen meridian. For Dampness in May (Aromatic Resolving Dampness Method from Shi Bing Lun) Take 3g each of Patchouli leaf (Huò Xiāng Yè) and Pèi Lán leaf, 4.5g aged tangerine peel (Chén Guǎng Pí), 4.5g processed Pinellia (Zhì Bàn Xià), 3g Areca peel (Dà Fù Pí, wine-washed), 2.4g Magnolia bark (Hòu Pò, ginger juice-fried), with 9g fresh lotus leaf (Xiān Hé Yè) as a guide. Decoct in water and take. For Damp-Warm Disease (from Shi Wen Da Lun) Take Pèi Lán, Patchouli (Huò Xiāng), Magnolia bark (Chuān Pò), Pinellia (Bàn Xià), Scutellaria (Huáng Qín), Coptis (Huáng Lián), Immature Bitter Orange (Zhǐ Shí), Talc (Huá Shí), and Coix Seed (Yì Rén). Decoct in water and take. For Early-Stage Warm-Heat Disease (Wu Ye Lu Gen Tang from Chong Ding Guang Wen Re Lun) Take 3g each of Patchouli leaf (Huò Xiāng Yè), Mint leaf (Bò He Yè), Pèi Lán leaf, and Lotus leaf (Hé Yè). First decoct 30g Loquat leaf (Pí Pá Yè), 30g Reed Rhizome (Shuǐ Lú Gēn), and 60g fresh Winter Melon (Xiān Dōng Guā) to make a base liquid, then use it to decoct the above herbs.
Daily Consumption
Pèi Lán Mouthwash: Take Pèi Lán alone in decoction or use the liquid as a mouthwash. It is particularly effective for halitosis. Patchouli and Pèi Lán Tea: Take 9g each of Patchouli (Huò Xiāng) and Pèi Lán, and 6g of green tea. Steep in boiling water, cover, and let steep for 5–8 minutes before drinking. This tea helps stimulate appetite, relieve vomiting, clear heat, quench thirst, relieve summer heat, and resolve dampness. Patchouli and Pèi Lán Congee: Take 15g each of Patchouli and Pèi Lán, decoct in water, and strain to obtain the liquid. Cook 100g of polished rice with the liquid. When the congee is almost done, pour in the herbal liquid and boil for 1–2 minutes. Suitable for summer heat, chest and epigastric stuffiness, vomiting, diarrhea, and poor appetite. Clear Vertigo Tea: Take 3g of Pèi Lán leaf, 8g each of Alisma (Zé Xiè) and White Atractylodes (Bái Zhú), 5g of Chrysanthemum (Jú Huā), and an appropriate amount of Lotus leaf stalk (Hé Yè Dì). Decoct in water and drink as tea. It helps resolve dampness, eliminate phlegm, and clear the head.
Medicinal Parts
Dried above-ground part.
Selection & Storage
Store in a dry container in a cool, dry place, protected from mold.