What is the horsetail plant used for?

Horsetail (Equisetum Arvense L) is a perennial plant of the Equisetaceae family, common in the northern hemisphere. Originally from Europe and northern Asia, it comes from the horsetails that formed large forests in the Mesozoic Era. It grows in clay or sandy soils, wild on the banks of rivers and in open fields, as long as the area is humid.

The sterile stems of horsetail are used and are collected at the end of summer. Due to its content of mineral salts, especially potassium, horsetail has a mild diuretic action. It can be taken in the form of an herbal tea (the herbal tea is the drink obtained by boiling certain combinations of herbs or spices in water, unlike an infusion, in which the water does not boil), in powder, in liquid hydroalcoholic extract ( drops) or in dry extract capsules at different concentrations. This plant, which can measure up to around eighty centimeters in height, is characterized by having two types of stems, some fertile and others sterile.

The fertile stems are so called because they contain the reproductive organs; They are the first to sprout from their underground rhizome, they appear at the end of winter and in spring, they are yellowish brown and end in large spikes that contain the spores. The sterile stems appear in mid-summer and die in the winter; They are hollow, grooved and articulated with numerous lateral branches.

Once the bundles of sterile stems have been cut, they resemble a horse's tail, hence its botanical name, equisetum, which comes from the Latin equus meaning "horse" and setum meaning "mane or bristle", which translated into Medieval Castilian as “cauda equina”, from which the current common name “horse's tail” comes.

The use of horsetail for medicinal purposes dates back to ancient times. Pliny the Elder (23-79 AD) cited that horsetail had hemostatic virtues and that its contact served to stop bleeding from wounds, and Galen (130-200 AD) already mentioned its diuretic properties. In the Middle Ages, the renowned doctor and religious Arnau de Vilanova describes that he used it to cure a fistula after having heard from another colleague about its healing properties.

Due to its content of mineral salts, especially potassium, horsetail has a mild diuretic action. Among the mineral salts, its high silicon content also stands out, which is why its powder, when ingested, is traditionally used as a remineralizer to strengthen hair and nails. Some authors argue that its richness in silicon can make horsetail useful as an aid in maintaining collagen in connective tissue, especially in the joints. Due to its content of flavonoids and other substances, it has antioxidant action.

It has also been observed in different scientific studies that, due to the volatile components it contains, it has antimicrobial action against different bacteria and fungi. The European Medicines Agency (EMA), in its monograph, contemplates its traditional use as a diuretic for “washing the urinary tract.” Other monographs, such as that of the German Commission E, also mention its healing properties, when used topically (on the skin) for wound healing. Traditionally, it is used, due to its mild diuretic property, as an aid in the treatment of overweight.

The Dosage recommended by the EMA (adults and adolescents over 12 years of age):

-Tisane: 2 to 3 g in 250 ml, 3 to 4 times a day.

-Powder: 570 mg, 3 to 4 times a day.

Horsetail, commercially, is also found in liquid hydroalcoholic extract form (drops) or in dry extract capsules at different concentrations. It is advisable not to exceed the doses recommended by the manufacturers. For external use, the German Commission E monograph recommends its use in the form of compresses or washes, from a herbal tea made with 10 g of sterile horsetail stems in 1 liter of water.

When the water boils, add the horsetail, leave for a couple of minutes, turn off the heat and let it rest until it is lukewarm. Strain and drink or use as a wash or compress. To drink, you can prepare all the herbal tea that will be used during the day, but it must be kept strained and covered. In this case, if you want to drink it hot, you must be careful that it does not boil again when heated. For external use, in compresses or washes, it is advisable to prepare each time it is going to be used.

Contraindications, adverse effects and recommendations:

-In case of hypertension or heart problems it should only be used under medical supervision.

-It should not be used with diuretic medications because it can enhance their effect and excessive diuresis is harmful. It should also not be used with antihypertensive medications without the supervision of a health professional (doctor or pharmacist).

-Its use is not recommended during pregnancy and lactation.

-In case of overdose, stomach pain, heartburn, nausea, vomiting, dry mouth, dizziness, confusion, palpitations, drowsiness or hypertension may appear.

-It should not be collected in the field if you do not have botanical knowledge, since Equisetum arvense can be easily confused with another very similar species, Equisetum palustre, of which, although the toxicity it can have on humans is not well known, there have been observed serious poisoning in herbivorous animals.

Informative note: the contents included in this section offer information related to existing therapies explained by specialists with experience in the field with an informative objective. In no case is it intended to take a position on its suitability or expressly promote its use.

Fountain. MAPFRE by María José Alonso Osorio, Member of Medicinal Plants and Homeopathy at the College of Pharmacists of Barcelona Collaborator with Advance Medical

Veride is a food supplement made with plants such as Horsetail, among others.