Horsetail

Stems of horsetail are used. It contains mineral salts (Sílicium, Potassium), flavonoids, caffeic acid, phenolic acids and sterols. Unproven effects are: diuretic and wound healing for burning injuries. Oral and topical use. ^{(Fitoterapia.net, EMA 2016, WHO 2010)}

On latest update no relevant published data on breastfeeding were found.

Side effects and toxicity have not been tested, therefore its use would be preferably avoided during breastfeeding or, as much, use it infrequently.

Topical use is compatible with breastfeeding whenever it not used on the nipple.

Prolonged or abusive use may produce hyponatremic dehydration ^{(Grim 2018)}, gastritis, vomiting, sea-sickness or stupor and hepatotoxicity ^{(Klnçalp 2012)}. May be confused with Equisetum palustre, which is toxic due to that it contains toxic alkaloids and thiaminase, and be cause of severe Vitamin B₁ deficiency ^{(Fitoterapia.net, Nowak 2022, Müller 2020)}. A case possibly related to the appearance of Autism after the prolonged use in pregnancy has been described. ^{(Ortega 2011)}

Precautions when taking plant preparations ^{(Anderson 2017, Powers 2015, Posadzki 2013, Efferth 2011, Kopec 1999, Hsu 1995)}:

• Make sure they are from a reliable source: poisonings have occurred due to confusion of one plant with another with toxic properties ^{(Hsu 1995)}, poisonings due to containing heavy metals extracted from the soil, and food poisoning due to contamination with bacteria or fungi. ^{(Anderson 2017)}
• Do not take in excess; follow the recommendations of expert phytotherapy professionals. “Natural” products are not good in any quantity: plants contain active substances from which much of our traditional pharmacopoeia has been obtained and can cause poisoning or act as endocrine disruptors if consumed in quantity or for an exaggerated time because they contain phytoestrogens. ^{(Powers 2015, Zava 1998)}