A weak immune system, stress, and an unbalanced diet can mess up your inner zen, wreaking havoc on your well being. One such manifestation of this imbalance is a canker sore—I routinely get them in the corner crevices of my mouth whenever I'm feeling depleted. The itching, burning unpleasantness isn't usually that visible, but feels dreadful, especially for such an unobtrusive ailment. The last thing you want to do is pick at a canker sore, putting yourself at risk for a bacterial or viral infection.
What Are Canker Sores?
A canker sore, (medical name, aphthous stomatitis) is a small mouth ulcer found typically in your mouth or inner cheeks. Sometimes, it can present in clusters and can be brought on by stress, a weak immune system, vitamin deficiencies, food sensitivities, food allergies, or tissue damage, and is exacerbated by poor oral hygiene and diet. Canker sores are not contagious.
Dr. Steve Gundry says canker sores are common, occurring in 20 percent to 60 percent of people. "People with a history of the condition," he says, "are more susceptible," explaining why I tend to get them with chronic fatigue. "While once thought to be caused by herpes viruses or other infectious agents, multiple studies have never found an infectious agent," he says. "Canker sores are totally different from fever blisters or cold sores of the lip."
Giuseppe Aragona, MD, adds that "Canker sores can be quite common in younger people and often heal themselves within a week. However, they can still appear in older people and can sometimes last more than two weeks. There are a multitude of reasons they can be caused, like stress, allergies or tissue damage."
To stave off the temptation to pick at your face, as aggravating a canker sore might leave a scar, we've tapped a variety of medical pros for 15 canker sore remedies you can try at home.
Meet the Expert
- Dr. Brian Kantor is a celebrity Cosmetic Dentist working out of Lowenberg, Lituchy & Kantor in NYC.
- Steven Gundry, MD is a microbiome expert, surgeon, pioneer in nutrition, as well as medical director at The International Heart and Lung Institute Center for Restorative Medicine.
- Giuseppe Aragona, MD, is a General Practitioner and Medical Advisor at Prescription Doctor.
- Dr. Lawrence Fung is a California-based Cosmetic Dentist and the founder of Silicon Beach Dental
- Derek B. Gatta is a board-certified prosthodontist and the co-founder of RiseWell.
- Dr. Ehsan Ali is a board-certified internal medicine physician based in Los Angeles.
Practice Proper Oral Hygiene
Sam Saleh, DDS, a cosmetic dentist and dental surgeon says, practicing proper oral hygiene will help prevent a canker sore from developing, and will remedy any developing lesions. "Floss and brush your teeth twice daily to remove possible irritants from the mouth that could trigger a canker sore," he says. Proper oral hygiene means brushing and flossing gingerly, to prevent oral injury. Avoid "scratching your gum with a finger nail while flossing," he says, and "try not to brush too aggressively following a dental procedure." Oral hygiene can prevent certain strains of "virulent bacteria that can lead to sore formation."
Avoid Cigarettes and Chewing Gum
Saleh says cigarettes, which can lead to tooth staining and loss, gum disease, and oral cancer, put you at higher risk for developing a canker sore. If you needed another reason to quit, abstaining from cigarettes during an outbreak can speed up recovery. "Smokers have a significantly higher chance of getting canker sores," he says. "Nicotine patches for the mouth and nicotine gum can also lead to the sores." If you have a canker sore, you should also avoid chewing regular gum, as this can exacerbate injury to the oral cavity.
Avoid Lectin at All Costs
Gundry suggests avoiding Lectin, or plant proteins found in foods like tomatoes, nuts, lentils, and eggplants. "I became intrigued by the similarity of these lesions to those of celiac disease lesions in the intestines as caused by gluten, when, as part of a Lectin free diet on my part, my recurrent canker sores vanished," he says.
Indeed, a study published in a 1991 medical journal, Medical Hypotheses, makes the "very strong association between lectins (of which gluten is just one) and the development of canker sores. One of the pleasant surprises for my patients with canker sores has been the complete permanent disappearance of canker sores by following a Lectin-free diet." He adds, "Interestingly, high acid foods like tomatoes or American dairy ( which contains the Lectin casein A1) have been associated with canker sores: it’s the high Lectin content of those foods that is the actual culprit."
If you can't rid your diet of Lectin, try a supplement like the GundryMD Lectin Shield to absorb most lectins in the diet.
Rub Chewable Aspirin on Any Existing Sores
Some over the counter methods can help alleviate pain associated with canker sores. Gundry recommends taking a "chewable 81 mg aspirin and allowing it to melt against the ulcer. I used this trick repeatedly when I used to get these ulcers. Gundry warns that an aspirin rub may be uncomfortable and burn, though it ultimately "leads to pain relief and rapid healing."
Take Your B12
Vitamin deficiency is linked to chronic canker sores. "If B12 needs are not being met through diet or supplements canker sores can develop," says Richards, "as this vitamin is necessary for cellular health." She adds that B12 is "naturally occurring in animal foods, but may also be found in fortified foods like those developed for vegan dieters. Some medical conditions can lead to a hindrance in B12 absorption, specifically Crohn's disease or celiac disease."
Or Swish With a Salt Water Rinse
Saleh recommends a warm salt water rinse for a canker sore remedy you can make at home with ingredients from your pantry. Dissolve one tablespoon of salt, preferably Himalayan salt, in 1/2 cup of warm water and swish for 15 to 30 seconds before spitting out. Repeat three to four times a day.
A natural detoxifying agent, pink Himalayan salt can balance pH, and encourage healing.
Support the Microbiome with Diet and Supplements
Maintaining a balance of bacteria in your gut, also known as the microbiome, is, as we know, essential for proper cellular function. To speed up the healing process, fortify your diet with gut healthy foods that repair and support the gut biome, like wild salmon, fermented vegetables, garlic, onions, and radishes.
You can also add a gut health supplement to your diet as an internal canker sore remedy.
Try Strengthening Your Immune System to Prevent Canker Sores
Considering canker sores are the result of a weakened immune system, it helps to focus on your health—paying special attention to your sleep schedule, exercise, and nutrition—in an effort to strengthen it. Take vitamin supplements for nutritional deficiencies. “While the exact cause of canker sores is unknown, these ulcers are seen in people with nutritional deficiencies, including low levels of zinc, folic acid, and iron, and especially vitamin b-12,” Kantor says. In fact, a 2015 study found that taking a vitamin B-12 supplement significantly reduced canker sore pain.
Avoid Acidic Foods and Food Sensitivities
"Certain foods can trigger canker sore development and even prolong its presence," says Lisa Richards, RD, author of The Candida Diet. "Acidic and/or spicy food can create canker sores in the mouth. The most common acidic foods that can lead to canker sores include citrus fruit and tomatoes." The idea is to balance the pH of the mouth and make keep oral inflammation at bay, especially when fighting a canker sore.
In addition to avoiding acidic foods, be aware if you have food sensitivities, as these might trigger a canker sore eruption. Richards says, "People with a sensitivity to coffee, eggs, nuts, chocolate, strawberries or cheese are prone to canker sores. This sensitivity makes their oral skin more apt to develop sores when these foods are eaten."
Rinse With Hydrogen Peroxide
Speaking of rinsing, Kantor says that swishing with hydrogen peroxide can be beneficial. “Rinsing your mouth with ingredients in your medicine cabinet can also relieve pain and irritation caused by a canker sore,” he says. “Take hydrogen peroxide, for example. It can minimize the amount of bacteria in your mouth.” For best results, he says to mix one part hydrogen peroxide with one part water. “Gargle the solution and then rinse out your mouth with water—don’t swallow hydrogen peroxide,” he advises.
Try an Over-the-Counter, Topical Gel
If your canker sore is, well, incredibly sore, it helps to apply an over-the-counter topical gel to help reduce irritation. “Canker sores respond positively to OTC topical creams designed specifically for oral lesions,” Kantor says. “These products include active ingredients—such as benzocaine and lidocaine—which reduce inflammation and promote healing.” What’s more, he says that they also act as a topical anesthesia to help alleviate pain. “Apply a cream or paste directly to the canker sore,” he instructs. “This provides a protective layer over the sore until it heals, so that eating and drinking don’t cause further irritation.”
Or Take Milk of Magnesia
While this medication is commonly used to relieve constipation, Kantor says that applying a small amount of milk of magnesia may also prove effective for canker sores, helping the lesions to heal faster. “Apply a small amount directly to the lesion a few times a day,” he instructs. “The medication will coat the canker sore, reducing irritation and pain.”
Switch to an Antiseptic Mouthwash
Don’t underestimate the power of a good mouthwash. “Rinsing the mouth with an OTC rinse can help keep the area clean and provide relief from pain or discomfort,” Kantor says. “You should use a mouth rinse with antiseptic properties. This can help prevent infection and numb painful sensations inside the mouth.”
There are many antiseptic mouthwashes on the market. A few of our faves include Oral-B Mouth Sore Special Care Oral Rinse ($9), Colgate Peroxyl Mouth Sore Rinse ($9), and Listerine Cool Mint Antiseptic Mouthwash ($7).
When in Doubt, Talk to Your Doctor About a Prescription
If these remedies don't provide the relief you need, ask your doctor for a sucralfate suspension to provide a protective barrier in the mouth, or a prescription for a corticosteroids elixir for persistent and especially menacing canker sores. Keep in mind that canker sores are a medical condition, and can only by prescribed and treated by a doctor. As such, speak to your physician before trying an at-home remedy.