Both sides of the mouth cracking may be infectious keratitis, traumatic keratitis, etc., the treatment is based on local medication, as follows. 1. Infectious keratitis: caused by fungi, bacteria, viruses and other microorganisms, fungal keratitis can be used locally miconazole ointment, bacterial infectious keratitis can be used locally gentamycin ointment, herpes keratitis can be used locally acyclovir ointment. 2. Traumatic keratitis: caused by trauma, physical stimulation, bad habits, etc., can be used locally compound boric acid solution wet compress, coated with povidone iodine. All of the above drugs need to be used under the guidance of a doctor. Both sides of the mouth cracking may have other reasons, it is recommended to go to the hospital in a timely manner, after a clear cause for targeted treatment.