Horsetail
Equisetum arvense
Family: Equisetaceae | Parts Used: Aerial stems
Horsetail is a prehistoric plant that has remained largely unchanged for over 300 million years. It is valued primarily for its exceptional silica content, which supports connective tissue, bone health, and skin repair. Traditionally used as a diuretic and vulnerary, its astringent properties also lend support for respiratory and prostate concerns.
Traditional Uses
- Managing incontinence and supporting urinary tract health
- Diuretic support for fluid retention
- Healing ulcers and wounds through vulnerary action
- Supporting enlarged prostate
- Respiratory support via astringent action on mucous membranes
- Structural strengthening of hair, nails, skin, and connective tissue through high silica content
Properties
Key Constituents
Preparations & Dosage
Cautions
- Contains thiaminase, an enzyme that depletes vitamin B1 (thiamine). Do not use long-term without B1 supplementation.
- May lower potassium levels; use with caution if taking diuretic medications.
- Not recommended for those with kidney or heart conditions.
- Avoid during pregnancy and breastfeeding.
- May interact with lithium and diabetes medications.
- Contains trace amounts of nicotine.
Habitat & Growing Conditions
Native to the northern hemisphere in temperate climates. Hardy in US zones 4-9. Prefers poor, sandy, or gravelly soil in wetland areas, streamsides, and disturbed ground. One of the oldest vascular plants on Earth, with fossil records dating back over 300 million years.
Related Articles
Sources & Research
Published Research:
Safety Assessment of Equisetum arvense-Derived Ingredients as Used in Cosmetics | International Journal of Toxicology (2026)
Functional Properties and Acceptability of Potentially Medicinal Tea Infusions Based on Equisetum arvense | Preventive Nutrition and Food Science (2023)
Phytochemical Investigation of Equisetum arvense and Evaluation of Their Anti-Inflammatory Potential in TNFa/INFy-Stimulated Models | Pharmaceuticals (2023)
Antihypertensive Effect of Equisetum arvense L.: A Double-Blind, Randomized Efficacy and Safety Clinical Trial | Evidence-Based Complementary and Alternative Medicine (2022)
These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease. If you are under the care of a health care provider or taking prescription medication, check with your provider before using any herbal supplement.