Marshmallow is most commonly used to ease sore throats and dry coughs. The Marshmallow plant, especially the leaves and roots, contains polysaccharides that have antitussive, mucilaginous, and antibacterial properties. Because of this, marshmallow has a soothing effect on inflamed membranes in the mouth and throat when ingested orally, specifically a sore throat. The antitussive properties help reduce dry coughing and prevent further irritation. Marshmallow leaf and root are used for pain and swelling (inflammation) of the mucous membranes that line the respiratory tract. They are also used for dry cough, inflammation of the lining of the stomach, diarrhea, stomach ulcers, constipation, urinary tract inflammation, and stones in the urinary tract.