Mouth ulcer patch has some therapeutic effects on mouth ulcers, as follows. The composition of oral ulcer patches is usually made of sodium carboxymethyl cellulose and sorbitol as the base, with the addition of chlortetracycline, chlorhexidine, surface anesthetics, glucocorticoids and so on, which can be anti-inflammatory and analgesic, and promote the healing of ulcers. Precautions for using mouth ulcer patches include. 1. limited to intraoral use. 2. Should not be used for a long period of time. If the symptoms do not improve after 1 week of continuous use, the medication should be stopped and medical attention should be sought. 3. Allergic to the patch is prohibited, allergic people should be cautious. 4. Prohibit the use of the patch when the shape of the patch changes. The adverse reactions and contraindications of this drug are not clear, it should be used under the guidance of a doctor, avoid self-medication.