Marshmallow (Althaea officinalis) root is rich in mucilage, a gel-like substance that coats and soothes mucous membranes. Herbalists have used this demulcent for centuries.
People reach for it to calm digestive complaints like mild heartburn or stomach upset, and to ease a scratchy throat or respiratory irritation. Others take it to moisten occasional dry coughs or soothe the urinary tract.
You can buy the dried root for tea, powder, capsules, or liquid extracts. A typical routine uses it two to three times daily between meals or when discomfort appears. Cold steeping the herb for several hours pulls out the most mucilage.
Take marshmallow at least one hour apart from medications, because the mucilage can slow drug absorption. Blood sugar levels may shift, so people with diabetes should monitor closely. Safety during pregnancy or breastfeeding is unclear. Avoid it during those times unless a healthcare professional advises otherwise.