Can i tell me how i can treat a prolonged canker sore?

If you have had it : For more than 2 to 3 weeks - please see your dentist for evaluation. F you have a canker sore ( aphthous ulcer) you can rinse your mouth w warm salt water. Mix a teaspoon of salt in 8 oz of warm water – gargle w this several times a day. Another option is to swish a mix of 1 part milk of magnesia ; 1 part liquid Benadryl (diphenhydramine) in your mouth. Spit out after about a minute. Avoid eating spicy food or food.