Canker sores can be treated by using an antimicrobial mouth rinse or corticosteroid ointment. While the pain generally lessens in a few days, pain relievers can be used to alleviate irritation, says WebMD.
There is no cure for canker sores, but they can be prevented by avoiding citrus fruits, acidic vegetables and spicy foods, as these may irritate the mouth, according to WebMD. Chewing gum can also cause irritation. Using soft-bristled toothbrushes after meals and flossing daily can help keep the mouth free of foods that may trigger a sore. A dentist should be contacted if a patient has sores that are unusually large, spread, last over three weeks, or cause intolerable pain or difficulty drinking fluids.
Canker sores are shallow ulcers in the mouth that cause discomfort. Simple canker sores can appear around four times a year and last up to a week. Typically, they occur in people between the ages of 10 and 20, claims WebMD. Complex sores are less common and occur most often in people who have had them previously. The exact cause is unknown, but stress and tissue injury are thought to be contributing factors. Certain cases of complex sores are caused by an underlying health condition such as an impaired immune system, nutritional problems, iron deficiencies or gastrointestinal tract diseases. In addition to the painful sores, severe attacks may cause fever, physical fatigue and swollen lymph nodes.