Compilation by Armando Gonzalez Stuart, PhD.

Scientific Name:

Equisetum arvense

Other Common Names:

Bottle brush, shave grass, cola de caballo, equiseto.

Parts of the plant used:

The fresh or green dried sterile shoots. The fertile shoots are not employed medicinally.

How is it used?

The stems are boiled in water to make a tea. Currently, there are also capsules, extracts and tinctures available.

What is it used for?

Horsetail has been used for centuries in many parts of the world as a diuretic (to promote urination) and to relieve minor urinary tract infections and for the treatment of kidney stones. This herb is also used to treat gastric ulcers and profuse (heavy) menstruation. Since it is one of the plants with the highest content of silica, it is used to slow down the process of osteoporosis (it is thought that silica strengthens bone), as well as to strengthen brittle fingernails. Externally, horsetail is applied as a skin antiseptic to treat minor infections, as well as to stop bleeding from minor cuts or wounds. Even though this herb continues to be used for a variety of ailments, very few of the herb’s purported benefits have been validated.


•Do not use during pregnancy and lactation, as this herb’s effects have not been adequately studied. •Horsetail is usually regarded as having low toxicity, although some species may contain a substance called thiaminase, which destroys vitamin B1 or thiamine. •Do not ingest teas made from this herb for prolonged periods of time without consulting a professional. •Do not use internally in small children due to its silica content. •Do not use in patients that have edema (accumulation of fluid under the skin) due to cardiac ailments. •Do not drink horsetail teas if you are taking cardiac stimulants (glycosides) such as Digitalis, as horsetail may increase their effects. •Do not use concurrently with diuretics (medications that increase urination) because potassium loss from the body may result. •Since horsetail contains variable amounts of nicotine, do not combine with products that contain caffeine or theobromine, since over stimulation of the nervous system may occur.


Before you decide to take any medicinal herb or herbal supplement, be sure to consult with your health care professional first. Avoid self-medication and self-diagnosis: Always be on the safe side!