Pei Lan

Eupatorium perfoliatum

Chemical Constituents

Eupatorin, astragalin, rutin, hyperoside, sesquiterpene lactones (eupafolin, euperfolitin, eufoliatin, eufoliatorin, euperfolide), heteroxylan polysaccharides, caffeic acid derivitives, pyrrolizidine alkaloids. [2][3][4]


3 to 9 grams dried herb prepared as directed. [1]



Traditional Use

Eupatorium perfoliatum is considered to be either acrid or neutral. It works through the spleen and stomach channels and is particularly useful in transforming dampness in the core body areas. The fragrance or aroma of this herb has a harmonizing effect and relieves symptoms such as nausea, abdominal distension, and stomach pain. E. perfoliatum also releases dampness associated with summertime disorders that present with chills, thirst and epigastritis. [1] 


Analgesic activity: 

In a controlled trial of 53 patients suffering from the cold virus, the experimental group was treated with the homeopathic preparation of E. perfoliatum and the control group with acetylsalicylic acid. All parameters measured were comparable in both groups. [5] 

Antimalarial activity:  

In an effort to identify future candidates that would be useful as anti-malarial agents, researchers examined the effectiveness of a homeopathic preparation of E. perfoliatum as a candidate for an anti-malarial drug. The preparation demonstrated significant inhibitory effect on parasite multiplication. [6] 

Immunostimulant activity:

Studies have reviewed the role of E. perfoliatum in immune function. In in vitro and in vivo settings, extracts of Pei Lan were compared to extracts of Echinacea angustifolia and two additional extracts. E. perfoliatum demonstrated stimulation of phagocytosis at 50% higher rate than Echinacea. [7] 

Cytotoxic activity: 

In a laboratory setting, E. perfoliatum extract demonstrated cytotoxic activity comparable to chlorambucil and mild antibacterial activity. [8] 


No documentation.

Interaction and Depletions

Interaction with other Herbs

No documentation.

Interaction with Drugs

No documentation.

Precautions and Contraindications

Side effects

Not to be used in those individuals suffering from Stomach Qi deficiency. [1] 

In large doses, Pei Lan is emetic and caution should be used.


Not to be used by pregnant or nursing women. 

Age limitation

Not to be used by children.

Adverse reaction

Use of this herb is restricted in some countries due to the alkaloid content and potential toxicity. However no formal toxicity studies have been conducted.


  1. D. Bensky, S. Clavey, E. Stoger, A. Gamble. Chinese Herbal Medicine Materia Medica, 3rd Edition. Seattle WA:Eastland Press;2004.477.
  2. H. Thomson. PDR for Herbal Medicines. Montvale, NJ: Thomson Healthcare Inc; 2007.
  3. M. Maas, F. Petereit, A. Hensel. Caffeic acid derivatives from Eupatorium perfoliatum L. Molecules. 23Dec2008;14(1):36-45.
  4. W. Herz, P.S. Kalyanaraman, G. Ramakrishnan. Sesquiterpene lactones of Eupatorium perfoliatum. J Org Chem. 24Jun1977;42(13):2264-2271.
  5. C.A. Gassinger, G. Wünstel, P. Netter. A controlled clinical trial for testing the efficacy of the homeopathic drug eupatorium perfoliatum D2 in the treatment of common cold. Arzneimittelforschung. 1981;31(4):732-736.
  6. G. Lira-Salazar, E. Marines-Montiel, J. Torres-Monzón, F. Hernández-Hernández, J.S. Salas-Benito. Effects of homeopathic medications Eupatorium perfoliatum and Arsenicum album on parasitemia of Plasmodium berghei-infected mice. Homeopathy. Oct2006;95(4):223-228.
  7. H. Wagner, K. Jurcic. Immunologic studies of plant combination preparations. In-vitro and in-vivo studies on the stimulation of phagocytosis. Arzneimittelforschung. Oct1991;41(10):1072-1076.
  8. S. Habtemariam, A.M. Macpherson. Cytotoxicity and antibacterial activity of ethanol extract from leaves of a herbal drug, boneset (Eupatorium perfoliatum). Phytother Res. Nov2000;14(7):575-577.