Polaprezine is a complex compound formed by zinc and L-carnosine. Zinc is an ideal carrier for L-carnosine. The two produce a significant synergy. After oral administration of the product, an insoluble compound is formed in the stomach to cover the ulcer surface and the ulcer edge tissues. Under the condition of not affecting physiological emptying, the compound maintains a long residence time in the stomach, thus playing a powerful and continuous barrier role on the damaged mucosa in the stomach, while creating a sound environment for repairing and healing the damaged mucosa.