Sores at the corners of the mouth may be associated with keratitis, impetigo, herpes simplex, etc. They can be treated with antifungal, anti-infective, and antiviral medications. 1. Keratitis: usually caused by pathogenic microbial infections, also commonly known as “rotten corners of the mouth”, manifested in local corners of the mouth redness, flaking, pus discharge, etc., may be associated with fungal infections, etc., the choice of mycobacterium mycoplasma ketoconazole cream and other drugs treatment. 2. Impetigo: it is a common bacterial infectious skin disease, which is prevalent in children, after diagnosis, you can choose to disinfect with iodophor, apply fusidic acid cream, mupirocin ointment, oral clindamycin, cefixime and other medications. 3. Herpes simplex: This is caused by herpes simplex virus infection, which may be transmitted through kissing or other close contact, and can be treated with antiviral medications, such as acyclovir ointment and penciclovir ointment, after diagnosis. It is recommended to consult a dermatologist in a hospital for the symptoms mentioned above, and the medication should be used under the guidance of a doctor, rather than blindly self-medication, in order to avoid adverse effects.