Lesser calamint was commonly used as a medicinal herb in medieval times, though is little used by modern herbalists. It is sometimes cultivated as a medicinal herb for household use. The whole plant is aromatic, diaphoretic, expectorant, febrifuge and stomachic. The leaves are harvested in July as the plant comes into flower and are dried for later use. An infusion is beneficial in cases of flatulent colic and weaknesses of the stomach, it is also used to treat depression, insomnia and painful menstruation. It should not be prescribed for pregnant women since in excess it can cause a miscarriage. Source: https://pfaf.org
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