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What is a canker sore? Why we get them and how to deal

Those blisters inside your mouth can be painful!
by Marguerite Ward / / Source: TODAY

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Have you ever woken up to find an annoying red or white bump inside your mouth or on your tongue? It might just be a canker sore, also known as an apthous ulcer.

The good news is that those painful growths are temporary. The bad news? There are a few factors that cause them — and there’s not necessarily a “cure.”

What causes canker sores?

Canker sores and cold sores are not the same thing. While cold sores are a result of herpes simplex virus type 1 (which about half of all Americans have), canker sores are unrelated to oral herpes.

Additionally, canker sores only appear on the inside of the mouth (sometimes on the throat too), while cold sores usually appear on a person's lip.

Dr. Melissa Piliang, a dermatologist at the Cleveland Clinic, explained more, “They tend to happen in kids, teens and young adults, usually between ages 10 and 20. And they happen more commonly in girls than boys. There are certain things that can bring them on or make them worse,” she said.

Hormonal changes as well as emotional stress can bring them out, Piliang said. Deficiencies in certain vitamins like B12, folate and iron are also linked to canker sore outbreaks.

More commonly, however, the culprit is an inner mouth injury or irritation.

“Some people get them when they get braces, when the edge of braces nicks the mouth. Or when someone gets hit with a ball, and makes a bump in the mouth, canker sores can develop at the sight,” Dr. Thomas Rohrer, a Boston-based surgical dermatologist told TODAY.

Spicy or acidic foods (think lemons, pineapples, oranges and even apples) can also irritate the mouth and lead to a growth, Rohrer added.

In addition, research suggests genetics can play a role in how often you get these annoying bumps. They may start to appear first in childhood or adolescence.

Mouth ulcer, canker sore, canker sore on lip, how to get rid of canker sores
A topical numbing cream or stronger medicine from a dermatologist can help with the irritation. Getty Images

How to get rid of canker sores:

You can’t really get rid of canker sores, as doctors say there isn’t a cure. Instead a topical, pain-relieving cream such as Orajel is probably your best bet. If you find you or your child’s braces are causing irritation and canker sores, request wax strips to apply to the metal to prevent scraping.

“If they’re bad and really bothering you, you can see a dermatologist who can give you a topical steroid which can help it go away faster,” Piliang said.

Canker sores should go away within one to two weeks. If they don’t, or keep appearing, see your doctor.

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