Equisetaceae
Horsetail
Equisetum arvense
✓ Generally Safe
Caution in Pregnancy
Native to: Europe, Asia, North America
Also known as: Common Horsetail, Field Horsetail, Shavegrass
Wikimedia Commons / CC BY-SA
Parts Used
Stem
Therapeutic Uses
Osteoporosis support (silica for bone density), brittle nails and hair, urinary tract disorders, prostate hyperplasia, wound healing, connective tissue weakness, kidney stones (prevention).
Herbal Actions
Remineralizing, diuretic, astringent, hemostatic, wound healer, connective tissue tonic
Active Constituents
Silica (5–8% as silicic acid and silicates), flavonoids (quercetin, kaempferol, isoquercitrin), saponins (equisetonin), alkaloids (traces), potassium, calcium
Preparation Methods
☕ Herbal Tea🏺 Tincture💊 Capsule
Traditional Preparation Notes
| Herbal Tea | 2 tsp dried herb per 250ml, simmer (not just steep) 15 min, 3x daily |
| Tincture | 3–5 ml (1:5, 25% ethanol), 3x daily |
| Notes | Simmering (not just steeping) required to extract silica. Standardized extract (7% silicic acid): 300mg 3x daily for bone and connective tissue. Do not confuse with Equisetum palustre (toxic). |
Safety Information
Safety Rating
✓ Generally Safe
Pregnancy
Caution in Pregnancy
Drug Interactions
Possible — consult doctor
Contraindications: Avoid in heart or kidney disease (diuretic, high potassium). May deplete thiamine with long-term use. Avoid with diuretics or cardiac glycosides.
Side Effects: Rare GI upset. Thiamine deficiency with extended use (contains thiaminase). Do NOT use Equisetum palustre — it contains toxic alkaloids.