Applying iodophor is not recommended for mouth ulcers. 1. Povidone-iodine is used medically as an antiseptic and disinfectant for the disinfection of skin and mucous membranes, as well as for the treatment of burns, trichomonas vaginitis, mycotic vaginitis, and mycotic infections of the skin. Povidone-iodine is a topical medication, prohibited for oral use, so it should not be used to coat the inside of the mouth. 2. The common concentration of medical povidone iodine is 1%, which can be used for skin disinfection treatment by direct rubbing; if it is used for stomatitis gargling, it needs to be diluted twice. An overdose of iodophor can cause corrosive gastroenteritis-like symptoms, with signs such as vomiting, vomiting blood, heartburn, blood in the stool, etc. It is recommended that this be done under the guidance of a doctor. Mouth ulcers may simply have due to trauma or tissue damage, such as tooth irritation, accidentally biting the inside of the cheek, but may also be a potential symptomatic manifestation of certain diseases, it is recommended that depending on the severity of the timely access to medical care, and comply with the doctor’s instructions for treatment.