Willow flower herb (Epilobium parviflorum) is a European perennial plant that is also known as small flowered willow herb. A member of the Onagraceae family, which has more than 160 different species, the willow flower herb has displayed antibacterial, antioxidant, and anti-inflammatory properties that may prove effective for men who have prostatitis or BPH.
Willow flower herb contains a number of active ingredients, including the flavonoids beta-sitosterol (which helps lower DHT), kaempferol, quercetin, and several types of ellagitannins–oenothein A and oenothein B. In studies conducted at the Prostate Center of Vancouver, scientists found that low concentrations of an extract from willow flower herb tea were active against abnormal cells and growths of the prostate. When extracts of willow flower were tested with the enzymes 5-alpha-reductase and aromatase, two enzymes involved with BPH, the scientists identified the components oenothein A and B as being active against these enzymes. (Ducrey 1997) The beta-sitosterol in willow flower herb is also helpful in reducing symptoms of BPH. (Berges 1995)
Researchers believe all willow herb species contain flavonoids, but some may be more potent than others. According to the results of an analysis published in the Journal of Pharmaceutical and Biomedical Analysis, E. parviflorum had the highest antioxidant capacity of various Epilobium species evaluated. (Hevasi Toth 2009) In a subsequent study (2010), the three most popular Epilobium species (E. angustifolium, E. hirsutum, E. parviflorum) were compared regarding their antioxidant and anti-inflammatory activities. Researchers reported that all the Epilobium preparations tested high in the level of oenothein B. (Kiss 2010)
In a study from the University of Pretoria, extracts of five herbal remedies for treatment of BPH and/or prostatitis were investigated for their antioxidant, anti-inflammatory, and antibacterial activities. Willow flower herb proved effective in all three activities, supporting its use for treatment of prostatitis and treatment of BPH. (Steenkamp 2006)
Willow flower herb is available as a tea and in proprietary blends. No standard dose of willow flower herb has been established and no side effects have been reported. Consult your healthcare provider before taking this herbal supplement.
Berges RR et al. Randomised, placebo-controlled, double-blind clinical trial of beta-sitosterol in patients with benign prostatic hyperplasia. Lancet 1995; 345:1529-32.
Ducrey B et al. Inhibition of 5 alpha-reductase and aromatase by the ellagitannins oenothein A and oenothein B from Epilobium species. Planta Med 1997 Apr; 63(2): 111-14
Hevasi Toth et al. Polyphenol composition and antioxidant capacity of Epilobium species. J Pharm Biomed Anal 2009 Jan 15; 49(1): 26-31
Kiss AK et al. Oenothein B’s contribution to the anti-inflammatory and antioxidant activity of Epilobium sp. Phytomedicine 2010 Nov 26
Steenkamp V et al. Studies on antibacterial, anti-inflammatory and antioxidant activity of herbal remedies used in the treatment of benign prostatic hyperplasia and prostatitis. J Ethnopharmacol 2006 Jan 3; 103(1): 71-75