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.

More recently, marshmallow has been used to treat certain digestive disorders, including heartburn, indigestion, ulcerative colitis, stomach ulcers and Crohn's disease. The mechanism by which it soothes sore throats applies to gastrointestinal mucosa as well and regular consumption of marshmallow can help with the pain of ulcerative colitis and Crohn's, and prevent stomach ulcers from perforation. Marshmallow extract is sometimes added to creams and used to treat inflammatory skin conditions, such as eczema and contact dermatitis. Additional uses are currently being investigated. Marshmallow may be a helpful aid to radiologic esophageal examination. There is tentative evidence that marshmallow may also help with respiratory disorders such as asthma. Researchers may soon test marshmallow as a natural alternative to blood sugar management in diabetes.