Silicon-Rich Diuretic

Scientific Name: Equisetum arvense (Equisataceae)

Common Names: pewterwort, bottle brush, horsetail glass, horsetail rush, scouring rush, shave grass

Description: This flowerless plant grows in moist environments around North America and Eurasia. Related to ferns, horsetails are primitive plants with scale-like leaves and hollow, branching stems. Known as bottle brush because of the silicon striations which make it a good scouring tool, this mild herb grows a flesh-colored stem bearing a spike of spores which is eventually replaced by a taller, sterile stem.

History: This plant grows to a maximum height of six feet and is commonly much smaller than its overgrown ancestors. Used as a matting rush and polishing agent by Native Americans, the horsetail was also used as a healing poultice. It was equally valued as a wound-healing ingredient by ancient Chinese physicians as well as by English renaissance herbalists. The soluble silica of horsetail’s external structure has helped make it historically useful in stopping bleeding—the silica is absorbed into the blood cells at the wound site which accelerates clotting and begins the healing process.

Modern Uses: With its various astringent and diuretic constituents, this perennial is often useful as a treatment for urinary tract ailments. Horsetail also possesses antibiotic properties valuable for healing internal wounds, as in the case of the urinary system, and also wounds found on the surface of the body. Horsetail’s much noted organic silica content, which has already been cited as a contributor to the herb’s blood-clotting efficacy, also encourages its inclusion as a frequent ingredient in skeletal enhancing formulas. Because the mineral is part of the human body’s processes for forming bone and other softer tissues, silicon ingestion, especially in such a bio-available form as horsetail, has traditionally been advocated at times of physical growth or during instances of necessary healing and repair to bone and cartilaginous structures. It has also been used to strengthen hair, skin and nails.

Still, horsetail’s primary use by many professional herbalists continues to be in the treatment of kidney and bladder disorders. A combination of horsetail sitz bath and horsetail tea is sometimes prescribed for the passage of kidney stones, and the ingested herb’s diuretic properties seem efficacious in treating other infectious diseases which lead to water retention. Even incontinence and bed wetting in children seems sometimes to find relief through horsetail-inclusive remedies. Additionally, the herb has earned some amount of popularity as an enhancer of the circulatory system, in part because it contains large amounts of silicon, potassium, calcium and a significant variety of fatty acids.

Recommendations: While this herb is traditionally and safely used to treat kidney-related ailments, its long term use may prove damaging to kidney function. Very excessive doses have led to poisoning in grazing animals, though not in humans. Care should also be taken to avoid internal damage due to rough silica scraping, also only in cases of exaggerated dosage. Make sure to achieve a high B vitamin intake to accompany a course of horsetail, since the herb encourages B vitamin breakdown.

General use is one or two capsules three times daily. For urinary tract problems it works best made into a decoction or strong tea.



A Handbook of Native American Herbs by Alma R. Hutchens (Boston: Shambhala, 1992).

Health through God’s Pharmacy by Maria Treben (Austria: Wilhelm Ennsthaler, Steyr, 1980).

Herbal Tonic Therapies by Daniel B. Mowrey, Ph.D. (New Canaan, Connecticut: Keats Publishing, Inc. 1993).

Herbs that Heal by Michael A. Weiner, Ph.D., and Janet Weiner (Mill Valley, California: Quantum Books, 1994).

Nutritional Herbology by Mark Pedersen (Warsaw, Indiana: Wendell W. Whitman Company, 1994).

Silica the Forgotten Nutrient by Klaus Kaufmann, Trophologist (Burnaby BC, Canada: Alive Books, 1990).

The Healing Herbs by Michael Castleman (Emmaus, Pennsylvania: Rodale Press, 1991).