I am facing recurrent mouth ulcer problem. what should i do?

Complex answer: Could be apthous ulcers ( canker sores) - these are not contagious and may respond to probiotics - especially if you are immunocompromised or have been on antibiotics. Usually concurring on cheek, tongue or floor of mouth. Might be herpetic lesions which are viral and respond to valtrex (valacyclovir). These appear as blisters and then ulcerate and are usually seen on lips and sometimes palate.

Could Be Stress: Stress is the cause for many problems including ulcers in the mouth. Those ulcers are viral in origin and can be triggered by trauma or stress.

Prevention: Canker sore or more specifically aphthous ulcer can be prevented by avoiding a common foam detergent found in most toothpastes called sodium laurel sulfate. Switching to biotene or other toothpaste not containing this ingredient can be the cure in preventing this painful condition.