Polygonaceae
Knotweed
Polygonum aviculare
✓ Generally Safe
Caution in Pregnancy
Native to: Worldwide (cosmopolitan)
Also known as: Common Knotgrass, Prostrate Knotweed, Wireweed, Doorweed
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Parts Used
Aerial parts
Therapeutic Uses
Diarrhoea, UTI, urinary gravel, respiratory catarrh, bronchitis (astringent expectorant), intestinal worms. Common weed with genuine therapeutic properties.
Herbal Actions
Astringent, diuretic, haemostatic, anti-inflammatory, remineralising (silica), anthelmintic
Active Constituents
Flavonoids (avicularin — primary, quercetin, myricetin, rutin), tannins, silica (high), caffeic acid, oxalic acid, vitamin C
Preparation Methods
☕ Herbal Tea🏺 Tincture
Traditional Preparation Notes
| Herbal Tea | 2 tsp dried herb per 250ml, steep 10 min, 3x daily with high fluid intake |
| Tincture | 3–5 ml (1:5, 25% ethanol), 3x daily |
| Notes | Common weed — free medicine. Silica content: remineralising. Traditional UTI and respiratory herb. Must drink high volumes of water. Combine with goldenrod for UTI. |
Safety Information
Safety Rating
✓ Generally Safe
Pregnancy
Caution in Pregnancy
Drug Interactions
None known
Contraindications: High oxalate — kidney stones, kidney disease. Avoid in pregnancy. Generally safe.
Side Effects: Reduced mineral absorption (tannins). Oxalate accumulation (large amounts). Very safe therapeutically.