Amoxicillin has no direct therapeutic effect on mouth ulcers. Mouth ulcers are usually recommended to be relieved with glucocorticoids or mouthwash. Mouth ulcers alone are localized pain and bleeding caused by a breakdown of the mucosal surface. Amoxicillin itself is mainly anti-inflammatory and anti-bacterial, so it can not be used to treat simple mouth ulcers. But if the mouth ulcer itself exists localized redness, inflammation or bacterial infection, then you can use amoxicillin for bacteriostatic treatment, this time can play an effective therapeutic effect. For simple oral ulcers can choose glucocorticoid ointment for topical application, such as tretinoin oral ointment, ketorolac acetate aminobutanetriol ointment, etc., can also choose mouthwash for local cleaning, such as rehabilitation of the new liquid, Xipay solid gum liquid, etc., can effectively promote the healing of the mucosal surface. After the appearance of mouth ulcers, it is recommended to choose the appropriate drugs under the guidance of a doctor for careful treatment, try not to use antibiotics without authorization.