Q: What causes canker sores? Why would I have a sudden outbreak of them in my mouth?
A: There are several theories about what leads to canker sores, those painful ulcers that form inside the mouth, on the tongue or inside the cheek or lips, although medical experts say they don't know the precise cause. They are distinct from cold sores, which form on the outer lip and are caused by infections with the herpes simplex virus.
Anyone can get a canker sore, although they occur more often in teenagers and young adults and may be more common in people with underlying medical conditions that cause inflammation or weaken the immune system.
"It's just one of those things where the exact cause has yet to be determined," said Dr. Sally Cram, a dentist and American Dental Association representative.
Among the possible culprits are viruses, bacterial infections, food allergies, poor nutrition, a weakened immune system and an injury or trauma to the mouth. Hereditary factors could also play a role.
Several studies have found people tend to have outbreaks of canker sores when they experience stress, which can take a toll on the immune system.
"A lot of people get canker sores if they have had a cold, been sick or really stressed at work, haven't been eating properly or haven't been getting enough sleep," Cram said.
Patients also tell her they developed sores after a mouth trauma, like accidentally biting one's cheek.
Most canker sores resolve on their own within one to two weeks. There is no cure, but over-the-counter anesthetic ointments or gels will ease the pain; you can find them in the drugstore's toothpaste aisle. Avoiding irritants such as alcohol, spicy food and foods with sharp edges, such as crackers, can also help ease discomfort.
See a dentist if you're concerned, and be frank about your medical history and medications. If you're having frequent or persistent outbreaks, get many canker sores all over your mouth or the sores are very large, you may want to investigate further. See your regular physician for a checkup to determine if you have an underlying illness, like diabetes or HIV infection, that may be weakening your immune system.
ActiveStyle on 04/16/2018