For daily wit & wisdom, get the Almanac newsletter.

How to Get Rid of Canker Sores (Mouth Ulcers)

Written By: Margaret Boyles Contributor

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!

Natural Remedies

About The Author

Margaret Boyles

Margaret Boyles

Contributor

Margaret Boyles is a longtime contributor to The Old Farmer's Almanac. he wrote for UNH Cooperative Extension, managed NH Outside (a writing collaborative for Extension natural resources volunteers), ...

Read more from Margaret Boyles

More Like This

Comments

<span>Tommy Holliday</span> Thu, 10/29/2015 - 16:34
I've been bothered with canker sores for years I've used Hydrogen Peroxide by dabbing some on with a Q'tip.
<span>Rachel Thomas</span> Thu, 10/29/2015 - 15:14
when I was young my parents had a container of potash. We dabbed that on with a Q -tip. Hurt like heck but was gone in a few days. But you cant get that anymore. I rinse with salt water two - three times a day. Works
<span>Monique L</span> Thu, 10/29/2015 - 13:42
I've had canker sores most of my life and I can say that I can finally take the control over them. I started take one Lysine supplement and when I see a canker sore started to show up, I take two daily; one in the morning and one at suppertime. I also rinse and gargle with half peroxyde/half water two or three times a day depending on the sensitivity of the canker sore. It never goes into a full blown canker sore anymore like it used to in the past. Good luck
<span>Dave Pistorius</span> Thu, 10/29/2015 - 13:21
Tea tree oil works very well. I used to have frequent canker sores. These days i rinse my mouth every day with tea tree oil. First I spray tea tree oil in my mouth and then add some water and rinse just like listerene. The sensation is exactly like listerene but much healty since there is no fluoride! I havent had any sores in years and even my chronic rhinitis is cured!! My mom recently had a canker sore, I asked her to apply tea tree oil. The sore was cured within 2 days! It had worked wonders for me!
<span>Lori Allred</span> Thu, 10/29/2015 - 12:52
I haven't had one in years but I rinse with salt water, stings but shortens them to a few days
<span>Jo</span> Thu, 10/29/2015 - 12:44
My mom always gave us alum powder for our canker sores. It takes the pain away. It tasted gross but it was the best treatment she found.
<span>Jennifer Zander</span> Thu, 10/29/2015 - 11:18
I've always used Alum powder. It's a pickling agent but it kind of numbs the area.
<span>Beverly Boardman</span> Thu, 10/29/2015 - 11:17
My mom had us use a touch of Alum powder on these . U talk about pain! But, U only had to suffer a few seconds, and no more pain with them .( Alum powder for pickling) . We would put up with the one time pain . so we wouldn't have to go through the long term discomfort. When the pain from the powder stops. Rinse mouth with cold water. All it takes is a tiny bit right on top of affected area. It really worked.!
<span>Jen Sam</span> Sat, 10/31/2015 - 09:14
Alum powder works the best!! Get a Q tip wet and apply to the sore- huge pain but it is brief! It then becomes numb and unaffected by foods or other stuff by next morning.
<span>Mollie Folmar</span> Thu, 10/29/2015 - 11:12
After having canker sores for years I recently found that taking folic acid every day keeps them away - along with some boil issues I had also. I am a believer in folic acid.