Licorice is the plant whose root has traditionally been used to soothe peptic ulcers and contains glycyrrhizin. The medicinal species most commonly meant is Glycyrrhiza glabra, a perennial legume native to parts of West Asia, Asia, North Africa, and southern Europe.
Glycyrrhizin is the root’s principal sweet-tasting glycoside and can account for roughly 7% to 10% of licorice root, depending on cultivation. It is a saponin that contributes much of licorice’s characteristic sweetness; purified glycyrrhizin is about 30 to 50 times sweeter than table sugar.
Licorice has a long history in herbal traditions and has been used for digestive complaints, including stomach irritation and ulcers. However, traditional use should not be confused with a guaranteed treatment, and modern ulcer care depends on the cause, such as Helicobacter pylori infection or nonsteroidal anti-inflammatory drugs.
A common mix-up is confusing licorice with anise, which may flavor candies but is a different plant. Excessive glycyrrhizin can lower blood potassium and raise blood pressure, so concentrated products can be risky for some people.