How to Get Rid of Canker Sores (Mouth Ulcers)


Canker Sore Causes and Treatment

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Ever had a canker sore? A type of mouth ulcer, these shallow white lesions are small and can appear anywhere inside the mouth, including the gums, tongue, and inside of the lips.  They can make eating and drinking mighty uncomfortable for a week or more. Here’s how to relieve canker sores.

What are Canker Sores?

Canker sores are whitish, red-bordered, slightly-cratered sores inside the mouth. Medical science knows that these commonly occurring sores by the somewhat frightening names, aphthous stomatitis, or aphthous ulcers. Women are more susceptible to canker sores than men, and some people seem more likely to get them than others.

The good news: unlike cold sores*, they aren’t infectious, so you can’t spread them to others or to other parts of your own body.

What Causes Canker Sores?

Brought on by stress, allergies, gluten sensitivity, hormonal changes, injury to the mouth, dental work, vitamin or mineral deficiencies, or—most commonly—unknown causes, canker sores typically heal without treatment within a week or two.

But experts recommend consulting your healthcare professional if:

  • A canker sore bleeds, oozes, or crusts over.
  • You experience fever or severe, long-lasting pain.
  • Your canker sore is unusually large and persistent.
  • You suffer frequently recurring canker sores, which may suggest an underlying disease.

How to Prevent Canker Sores

To help prevent recurrent canker sores, healthcare professionals suggest:

  • Avoiding toothpastes containing sodium lauryl sulfate.
  • Reflecting on what trigger foods or drinks might be the culprit. Common triggers: walnuts, strawberries, eggs, cheese, chocolate, spicy foods.
  • Consulting your orthodontist if sharp edges on braces, dental retainers, or other dental appliances irritate your mouth.

Canker Sore Remedies

You can choose from a variety of prescription and over-the-counter products to soothe the pain and accelerate healing. I suffered a series of painful canker sores last winter, before discovering my increased intake of walnuts as the culprit.

My favorite natural remedy: a soothing cup of warm sage/chamomile tea, swooshing it around as a mouthwash while I sipped.

Another remedy is to simply rinse your mouth with baking soda (dissolve 1 teaspoon of baking soda in 1/2 cup warm water).

It also can help to blot your sores with milk of magnesia a few times a day.

To find relief from pain, let some ice chips dissolve in your mouth.
Also, be sure to use a very soft toothbrush and try a sensitive toothpaste, nothing abrasive.

* Don’t confuse canker sores with cold sores. Cold sores (“fever blisters”), caused by the herpes simplex virus, occur on the outside of the mouth, typically on or around the lips. Often brought on by stress or hormonal changes, they appear as red, painful, fluid-filled blisters that are highly contagious. See how to treat cold sores!

About The Author

Margaret Boyles

Margaret Boyles is a longtime contributor to The Old Farmer’s Almanac. She wrote for UNH Cooperative Extension, managed NH Outside, and contributes to various media covering environmental and human health issues. Read More from Margaret Boyles

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