encyclopedia

Willowherb, Small Flowered

Scientific Names:
Epilobium parviflorum SCHREBER [Fam. Onagraceae]

Forms:
Tea and extracts from stems and leaves of Epilobium parviflorum L.

Traditional Usage:
– Antibacterial
– Anti-inflammatory
– Antimicrobial
– Antioxidant
– Benign Prostatic Hyperplasia (BPH)
– Bladder Health Maintenance
– Cellular Regeneration
– Cleansing
– Detoxification
– Hormonal Imbalances
– Male Health Maintenance
– Prostate Health Maintenance
– Urinary System Problems

Overview:
Small-flowered willowherb, Epilobium parviflorum SCHREBER [Fam. Onagraceae], is widespread in Central and Eastern Europe and in disturbed areas of North America. Epilobium species have been used as remedies in folk medicine, particularly in Central Europe, for the treatment of prostate disorders and abnormal growths. This pleasant herb and flower tea was highly recommended by Austrian herbalist, Maria Treben, for ailing men with prostate abnormalities. Based on customer feedback to health food stores and companies in Canada and the U.S., small-flowered willowherb quickly helps men to recover from the annoying symptoms of prostatitis. Preliminary (in vitro) studies at the Prostate Center of Vancouver found that very low concentrations of an extract from small-flowered willowherb tea, in the micrograms per ml level, was among the most active ever seen against abnormal cells and growths of the prostate. Several extracts from Epilobium parviflorum, were evaluated in biochemical assays with 5-alpha-reductase and aromatase, two enzymes involved in the etiology of benign prostatic hyperplasia (BPH). Aqueous extracts displayed inhibition of these enzymes and the active compounds identified were macrocyclic ellagitannins, oenothein A1, B1 and B2, which can make up to 14% of crude plant extracts. Out of a total of 92 plant phenolic extracts tested, small-flowered willowherb was also found to have high antioxidant activity. Small-flowered willowherb tea is also recommended for treating urinary tract infections in women. In one study, both the large-flowered willowherb (Epilobium angustifolium) and small-flowered willowherb E. parviflorum were found to reduce inflammatory prostaglandins in the carrageenin-induced rat paw edema test; in this study, E. angustifolia was found to be 5 times more powerful than E. parviflori. Antimicrobial screening of 13 phenolic substances and 29 extracts prepared from Finnish plant materials against selected microbes found that willowherb (Epilobium angustifolium L.) was one of the most active plant extracts tested against bacteria.

Active Ingredients:
As far as known, all willowherb species contain flavonoids, especially derivatives of kaempferol, quercetin, and myricetin. In E. parviflorum and E. angustifolium, b-sitosterol, various esters of sitosterol, and sitosterol glucoside have been detected. Gallic-acid derivatives may be present. Two macrocyclic ellagitannins, oenothein A (1) and oenothein B (2), have been identified as the main constituents responsible for the inhibition of 5-alpha-reductase and aromatase enzymes. Quantitation of oenothein B in 10 different species of Epilobium has shown that amounts of up to 14% in the crude plant extracts are possible. [Ducrey B, Marston A, Gohring S, Hartmann RW, Hostettmann K. 1997. Inhibition of 5 alpha-reductase and aromatase by the ellagitannins oenothein A and oenothein B from Epilobium species. Planta Med 1997 Apr; 63(2): 111-4].

Suggested Amount:
Willowherb can be taken as a tea. To make the infusion pour boiling water over 1.5-2 grams (1 teaspoon = 0.8 grams) of finely chopped willowherb, steep for 10 minutes, then strain.

Drug Interactions:
None known.

Contraindications:
None known.

Side Effects:
None known.

References:

Hiermann A, Juan H, Sametz W. 1986. Influence of Epilobium extracts on prostaglandin biosynthesis and carrageenin induced oedema of the rat paw. J Ethnopharmacol 1986 Aug; 17(2): 161-9.

Kahkonen MP, Hopia AI, Vuorela HJ, Rauha JP, Pihlaja K, Kujala TS, Heinonen M. 1999. Antioxidant activity of plant extracts containing phenolic compounds. J Agric Food Chem 1999 Oct; 47(10): 3954-62.

Lesuisse D, Berjonneau J, Ciot C, Devaux P, Doucet B, Gourvest JF, Khemis B, Lang C, Legrand R, Lowinski M, Maquin P, Parent A, Schoot B, Teutsch G. 1996. Determination of oenothein B as the active 5-alpha-reductase-inhibiting principle of the folk medicine Epilobium parviflorum. J Nat Prod 1996 May; 59(5): 490-2.

Rauha JP, Remes S, Heinonen M, Hopia A, Kahkonen M, Kujala T, Pihlaja K, Vuorela H, Vuorela P. 2000. Antimicrobial effects of Finnish plant extracts containing flavonoids and other phenolic compounds. Int J Food Microbiol 2000 May 25; 56(1): 3-12.

Wichtl M and NG Bisset (eds). 1994. Epilobii herba – Willowherb. In Herbal Drugs and Phyto-pharmaceuticals. (English translation by Norman Grainger Bisset). CRC Press, Stuttgart, pp.185-187.