Montmorillonite is not generally used for the treatment of mouth ulcers. It is a bulk made of montmorillonite, which is mainly used for the treatment of gastrointestinal disorders and can be adsorbed on the intestinal mucosa to protect the intestinal mucosa and adsorb pathogenic bacteria. The causes of mouth ulcers may be related to a variety of factors, such as local trauma, infection, autoimmune dysfunction, mental factors, neurological factors, suffering from underlying diseases, etc. The general principle of treating mouth ulcers is to remove the cause, topically with drugs that prevent infection and promote wound repair, there are more types of drugs, such as nourishing yin and generating muscles has a good therapeutic effect; you can also use patches, such as dexamethasone patches, gentamicin-type patches, which are effective in treating mouth ulcers and belong to special drugs. The prescription instructions for montelukast do not state that it is used for the treatment of mouth ulcers, and there is no clear report that montelukast can treat mouth ulcers, so it is recommended to use standardized and recognized drugs for the treatment of mouth ulcers for treatment is more secure and more effective.