recently my  brother  has sore type  under his tongue after preliminary investigation  doctors conclusion was that is due to bacterial infection and he started antibiotics for weeks it totally disappeared .After fortnight it again appeared what might be the reason and what is the treatment to be taken .
Hello and Welcome to Ask A Doctor service. I have reviewed your query and here is my advice. A sore under tongue can be a canker sore or yes, it can be bacterial infection as it went away completely after treatment with antibiotics. There is a possibility that the infection was not completely resolved, and it is the cause of the recurrence. So it is better to take another course of antibiotics. Along with it do warm saline gargles, antiseptic mouthwash gargles and take vitamin B complex for a week. Hope I have answered your query. Let me know if I can assist you further.