Horsetail (Equisetum arvense)

This herb is approved for treatment of wounds and burns. The major active compound is the astringent silicic acid which comprises 5.0—7.7% of the extract by weight. Flavonoids such as apigenin glucoside contribute to the astringent effect. Other actives are caffeic acids including chlorogenic acid and pyridine alkaloids such as nicotine. Horsetail should not be used in patients with cardiac or renal compromise even topically (13). The liquid extract is administered as a decoction or tea for infusion or compress (3).