Willow Herb refers to several species of the Epilobium genus — particularly Epilobium parviflorum — that grow wild across Europe, the Alps, Eastern Europe, and Siberia. Despite being relatively unfamiliar in mainstream Western supplements, it has been used for centuries by Alpine herbalists, Austrian naturopaths, and Siberian traditional healers. The plant is especially prized for its effects on the male urinary and reproductive system.

Willow Herb appears to work through several complementary pathways: its key compound oenothein B inhibits both 5-alpha-reductase (the enzyme that converts testosterone to the more potent DHT, which drives prostate tissue growth) and aromatase (the enzyme that converts androgens to estrogens). By dialing down these two enzymes, it may help slow prostate enlargement and reduce inflammation in the gland. Its flavonoids and tannins add further anti-inflammatory and antioxidant support to the urinary tract.

Traditional use is as an herbal tea from dried leaves and flowers. Modern supplements are available as capsules with standardized dry extracts (often standardized to polyphenol or oenothein B content) and as liquid tinctures. Standardized extracts offer more consistent dosing. Tea is gentler and well-suited for long-term daily use.

• Enlarged prostate (BPH)
• Prostate inflammation (prostatitis)
• Frequent or weak urination in men
• Nighttime urination (nocturia)
• Urinary tract inflammation
• Bladder irritation and discomfort
• Hormonal balance in aging men
• Antioxidant support and cellular protection
• Digestive inflammation and gut discomfort

• May help slow progression of early BPH when used long-term as part of a prostate health routine

• Pomegranate juice or seeds — Among the richest dietary sources of ellagitannins — the same polyphenol class as oenothein B — supporting similar anti-inflammatory and aromatase-modulating effects
• Pumpkin seeds — Rich in beta-sitosterol and zinc, both of which support prostate tissue health and urinary flow, complementing Willow Herb's mechanisms
• Cooked tomatoes — High in lycopene, a well-studied antioxidant that supports prostate health and may reduce prostate inflammation
• Walnuts — Provide plant phytosterols and anti-inflammatory omega-3 fatty acids that support healthy androgen metabolism in aging men
• Green tea — Contains EGCG and other flavonoids that work on overlapping anti-inflammatory and antioxidant pathways in prostate tissue

• Mild digestive upset or nausea (rare, usually with concentrated extracts on an empty stomach)
• Loose stools or mild diarrhea (at high tannin doses from tea)
• Allergic skin reactions in people sensitive to plants in the Onagraceae family (rare)
• Theoretical hormonal effects at very high doses due to aromatase and 5-alpha-reductase inhibition — not reported clinically but worth considering in sensitive individuals
• No significant hepatotoxicity reported in traditional use or available clinical literature

• Recommended daily: Dried herb tea: 1–2 teaspoons (2–4 g) of dried herb steeped in hot water, 1–3 times daily. Standardized extract (capsule): 200–400 mg per day, often standardized to polyphenol content. Tincture (1:5): 2–4 mL up to three times daily. Doses used in European herbal practice typically equate to 4–8 g dried herb equivalent per day for active BPH support.
• Best time of day: No strict timing requirement; taking with meals may reduce any digestive sensitivity. Tea form can be taken morning and evening as part of a routine.
• With or without food: Preferably with food to minimize any gastric sensitivity, especially with concentrated extracts or tinctures
• Time to effect: Urinary flow improvements may be noticed in 2–4 weeks; fuller prostate symptom relief typically requires 6–8 weeks of consistent use
• How long to take it: May be used long-term for ongoing prostate support. Traditional use involves daily tea consumption over months or years. No formal cycling protocol is established, but periodic reassessment (every 3–6 months) with a healthcare provider is sensible for men managing BPH.