Mouth rotting is considered to be the emergence of keratitis, but also may have a certain relationship with oral ulcers, need to use medication under the guidance of a doctor. 1. Keratitis, some patients with keratitis due to infection in the corner of the mouth, there may be symptoms of mouth rot, accompanied by redness, swelling, pain and other reactions. If it is a bacterial infection, you can use tretinoin ointment, erythromycin ointment and other drugs under the guidance of the doctor, if it is caused by a fungal infection, you can use clotrimazole cream, miconazole cream and other drugs. 2. Mouth ulcers, some patients with mouth ulcers after the oral parts of the erosion, may appear this symptom, can be used under the guidance of the doctor vitamin C, cidadeine tablets and other medication. Usually need to do a good job of daily care health care work, light diet.