Marsh mallow is a very useful household medicinal herb. Its soothing demulcent properties make it very effective in treating inflammations and irritations of the mucous membranes such as the alimentary canal, the urinary and the respiratory organs. The root counters excess stomach acid, peptic ulceration and gastritis. It is also applied externally to bruises, sprains, aching muscles, insect bites, skin inflammations, splinters etc. The whole plant, but especially the root, is antitussive, demulcent, diuretic, highly emollient, slightly laxative and odontalgic. An infusion of the leaves is used to treat cystitis and frequent urination. The leaves are harvested in August when the plant is just coming into flower and can be dried for later use. The root can be used in an ointment for treating boils and abscesses. The root is best harvested in the autumn, preferably from 2 year old plants, and is dried for later use. The German Commission E Monographs, a therapeutic guide to herbal medicine, approve Althaea officinalis Marsh Mallow for irritation of mouth and throat and associated dry cough/bronchitis (Root and leaf), mild stomach lining inflammation. Source: https://pfaf.org/
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