There is no fastest remedy for rotting mouth. Rotten mouth refers to keratitis in medicine, which can be improved by local medication, oral medication and lifestyle adjustment. 1. Topical medication: if the lack of vitamins caused by keratitis, you can apply vitamin B1, vitamin B6, etc. under the guidance of the doctor. If the keratitis is caused by virus, you can apply aciclovir ointment topically. 2. Oral medication: patients with severe bacterial infections can choose to take antibiotics such as tetracycline for treatment. 3. Adjustment of lifestyle: attention should be paid to do a good job of cleanliness and hygiene of the affected area of the corners of the mouth. And also pay attention to avoid opening the mouth significantly, and do not touch and pick the scabs on the affected area. If diagnosed with keratitis, should immediately go to the hospital for examination, under the guidance of a professional doctor to choose targeted treatment, to avoid blindly using drugs to cause adverse consequences.