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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

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Comments

<span>Lancem</span> Thu, 10/29/2015 - 21:10
If you can handle the few seconds of pain, you can use a Silver Nitrate stick to chemical burn the sore. You will have to get a perscription to buy them and you have to be Very Careful using the stick. After the initial pain, there is no more pain and I think they heal faster.
<span>Jean Nadler</span> Thu, 10/29/2015 - 20:23
Old remedy is to apply tooth paste several times a day, it will be gone in a couple days. The tooth paste taste better than alum and heals just as fast. Of course you have to use tooth that contains a form of alum
<span>Cathy Rodgers</span> Thu, 10/29/2015 - 19:58
I've had canker sores all my life, usually related to excess consumption of acidic foods and/or excessive stress (which raises the acid level in the body). The one thing that consistently works overnight to eliminate the canker sore, is to swish and rinse my mouth thoroughly with a mixture of equal parts hydrogen peroxide and water. I keep a small medicine cup (about 1 oz., the kind that comes with kids' cough medicine) in my cabinet with a bottle of peroxide. If I have a canker sore, or notice on coming on, I fill the cup halfway with peroxide and add water to the top. Then I swish the cupful of liquid in my mouth for about 15 seconds after I brush my teeth, right before I go to bed. The canker sore no longer hurts when I wake up, and is often gone by the morning. If it isn't, I repeat the procedure the following night and it will be.
<span>Sonny Usher</span> Thu, 10/29/2015 - 19:55
Kenalog steroid paste always works
<span>Philippa Goodman</span> Sat, 10/31/2015 - 04:02
As a dental practitioner, I agree, avoid SLS toothpaste, and use Kenalog ointment from the pharmacy (it contains a small amount of cortisone in an or or orabase to accelerate healing)
<span>Janice Millikan</span> Thu, 10/29/2015 - 19:55
We use Alum with great success. It is a pickling spice.
<span>Jimmyf</span> Thu, 10/29/2015 - 19:11
I've had them my entire life, I use to get 4 or 5 at a time. Now I only get them when I bite my cheek or lip unfortunately it happens frequently. I use kanka to numb it, it burns like the dickens but when you get them severely an hour of comfort is worth it. Then I was introduced to L-Lysine, you can by this anywhere herbs or vitamins are sold, I get mine at Walmart. Take it regularly and your canker sores will become a rarity in your life. I don't get them like I used to so I don't take it regularly, but when one starts to come up I'll take L-Lysine for a few days and it will kill it and the spot will start going away. Or you can go to the Dr and get silver nitrate sticks but that is the worst pain ever but they will make it dead instantly.
<span>Lisa N</span> Thu, 10/29/2015 - 18:56
Put Vaseline on it to keep it from chafing against teeth while it heals.
<span>Teresa Fermin</span> Thu, 10/29/2015 - 18:55
Use a very tiny dot of ALUM directly on the canker sore. And I do mean a tiny bit. Use a wet Q-tip and just barely dot some on it. Hold the lip or cheek out away from teeth and gums for a few minutes and let the drool spill into the sink or a cup or something because there will probably be some saliva produced. It cauterizes it. This will heal a canker sore in one day.
<span>Bart Robinson</span> Thu, 10/29/2015 - 18:11
Canker sores a.k.a. Mouth Ulcers were always treated with Borax powder, mum would lick her finger and dip it into Borax, then dab the powder onto it. Worked too!