Canker Sores: Causes, Remedies, And Preventive Measures

Written by Monomita Chakraborty

Canker sores are one of the most prevalent types of oral ulcers that form inside the mouth and at the base of the gums. These small and shallow lesions are not contagious but can be painful and cause discomfort while eating and talking. While the exact reasons for canker sores are unknown, factors like stress, injury, certain foods, and medicines may trigger them.

Home remedies and over-the-counter (OTC) medications may aid in pain relief and the recovery process. Keep scrolling to understand how you can get rid of canker sores with home remedies and prevention tips to follow.

What Is A Canker Sore?

What Is A Canker Sore


Canker sores or aphthous ulcers are shallow ulcers that occur on soft tissues inside the mouth (1). They commonly look like reddish swellings with white or yellow tips. Canker sores are non-contagious. However, they can be painful and cause discomfort while eating and talking.

Minor canker sores usually go away on their own, but large and persistent ones may require medical care. These are not dangerous, and home remedies may help relieve the pain and irritation.

Read the next section to find out common home remedies for canker sores.

Ways To Get Rid of Canker Sores: 14 Home Remedies To Try

1. Salt Water Rinse

A saline rinse is a popular home remedy tested by many people to reduce pain and discomfort associated with oral sores.


1. Dissolve a teaspoon of salt in a cup of warm water.
2. Swish it in the mouth for 30 seconds and spit.
3. Repeat every few hours.

2. Honey

Honey can help reduce the pain, discomfort, and size of minor canker sores (2). Use raw and unpasteurized honey for best results.


1. Apply raw honey to the sore and leave it on.
2. Repeat four times a day.

3. Alum Powder

Alum powder is a preservative used to pickle fruits and vegetables. It can significantly decrease the size of canker sores and reduce pain and discomfort caused by them (3).


1. Mix a pinch of alum powder with a drop of water to make a paste.
2. Apply the mixture to the canker sores.
3. Leave it on for at least a minute and rinse well.
4. Repeat this process once or twice every day until you see results.

4. Baking Soda

Baking soda is commonly used to reduce swelling, pain, and redness caused by canker sores.


1. Dissolve a teaspoon of baking soda in a cup of water.
2. Swirl it for 30 seconds in your mouth and spit it out.
3. Repeat every few hours.

5.Aloe Vera

Aloe vera gel reduces canker sore pain and speeds up the healing process (4).


1. Apply pure aloe vera gel to the canker sore.
2. Leave it on for a few minutes and wash it off.
3. Repeat every few hours.

6. Apple Cider Vinegar

Apple cider vinegar is a common home remedy to soothe inflammation and redness caused by canker sores.


1. Mix a tablespoon of apple cider vinegar and two tablespoons of water.
2. Apply the solution to the canker sore with a cotton swab.
3. Repeat once or twice a day.

Note: Excess use of vinegar may damage the tooth enamel.

7. Hydrogen Peroxide

The hydrogen peroxide solution is also a common home remedy to clean the sore and reduce bacterial growth in the mouth. However, it may sting a little.


1. Dilute a tablespoon of 3% hydrogen peroxide solution with a tablespoon of water.
2. Apply the solution to the canker sore with a cotton ball.
3. Leave it on for a few minutes and wash it off.
4. Repeat twice a day.

8. Coconut Oil

Coconut oil contains lauric acid that has antimicrobial and anti-inflammatory properties. It can help reduce inflammation caused by canker sores and maintain oral hygiene (5).


1. Apply a few drops of virgin coconut oil to the canker sore.
2. Leave it on, and do not wash it off.
3. Repeat every few hours.

9. Chamomile

Chamomile tea can reduce inflammation and pain associated with mouth ulcers and canker sores (6).


1. Apply a chamomile tea bag to the canker sore as a warm compress.
2. Hold it for a few minutes.
3. Repeat the process 3-4 times a day.
4. You may also drink a cup of chamomile tea with honey for relief.

10. Watermelon Frost

Watermelon frost is a common traditional Chinese home remedy for soothing canker sores. It is available in spray, tablet, and powder forms and helps reduce inflammation.


1. Apply (or spray) the watermelon frost powder (or solution) to the canker sore.
2. Leave it on for a few minutes and wash it off.
3. Repeat not more than twice a day.

Note: Excessive use of watermelon frost is associated with mercury poisoning and may cause side effects like skin rashes and motor tics (like involuntary eye blinking, head-turning, and shrugging) (7). Hence, practice caution.

11. Vitamin B12 Supplements

Canker sores are often caused by vitamin B12 deficiency. In such cases, taking vitamin B12 supplements may help relieve mouth ulcers (8), (9). However, this treatment may work if you have a deficiency. Do not self-medicate and consult a doctor before taking vitamin supplements.

12. Ice Cubes

Rubbing ice on the sore may have a numbing effect and help relieve the pain and inflammation caused by canker sores.


1. Crush the ice cubes. Wrap them in a piece of cloth.
2. Apply the cold compress to the canker sore.
3. Repeat 2-3 times a day.

13. Garlic

Garlic is a well-known natural remedy for healing canker cores. It contains allicin that reduces inflammation and promotes healing (10).


1. Rub a small piece of garlic on the canker sore for 3-5 minutes.
2. Leave it on for 20 minutes and then wash it off.
3. Repeat twice or thrice a day.

14. Echinacea Tablets

Echinacea tablets are an herbal remedy for treating canker sores. They can reduce pain and lesion count to promote healing (11). However, consult a herbalist or a doctor before trying this remedy.

Canker sores can be bothersome, but you can heal them at home with these tips and remedies. Oral hygiene is a crucial factor in preventing them. Check out the next section to learn more.

How To Prevent Canker Sores

  • Brush and floss your teeth at least twice a day to keep out food particles and prevent bacteria growth and plaque formation.
  • Avoid excessive use of oral hygiene products containing sodium lauryl sulfate. It may dry out and irritate the delicate mucus membrane.
  • Avoid excessive spicy foods, acidic fruits, and other acidic beverages.
  • Use a soft-bristled toothbrush to prevent injuring the gums (if you get canker sores often).

The exact reasons for canker sores are not known. However, certain factors are believed to trigger mouth ulcers.

Canker Sores: Causes And Risk Factors

Factors that can increase the likelihood of developing canker sores are:

  • Family history
  • Consuming acidic foods
  • Infections
  • Vitamin and mineral deficiencies
  • Hormonal imbalance
  • Allergies
  • Stress
  • Sleep deprivation
  • Oral injuries (caused by bites, improper brushing, and dental appliances, such as braces and dentures)

Canker sores usually heal on their own. However, in some cases, you may have to visit a doctor.

It is a good idea to contact a doctor or dentist if a sore hasn’t healed in two weeks or the irritation is severe. They will look at the inside of your mouth and ask you about any additional symptoms you are having and your dietary habits.

A swab test, blood test, tissue sample, or inspection of particular organs may be necessary if they suspect another condition is causing the sores.

When To See Your Doctor

If the canker sores do not go away within a few days and persist for over two weeks, visit a doctor immediately. You may need immediate medical attention if the pain is unbearable and is accompanied by:

  • Fever
  • New sores
  • Infection
  • Sore lips
  • Pus

Many times mouth and gum infections (like gingivostomatitis) may resemble canker sores. Visit a dentist for proper diagnosis and treatment.

The Takeaway

Canker sores are a common issue, usually go away on their own, and do not require medical treatment. However, they often cause pain and discomfort that can be managed with common home remedies. You can try the remedies discussed in the article. However, if the ulcers persist over two weeks, it might indicate other underlying oral conditions and infections. In such cases, visit a doctor immediately for proper diagnosis and treatment.

12 Sources

Articles on StyleCraze are backed by verified information from peer-reviewed and academic research papers, reputed organizations, research institutions, and medical associations to ensure accuracy and relevance. Read our editorial policy to learn more.

  1. Aphthous Stomatitis
  2. Efficacy of honey in comparison to topical corticosteroid for treatment of recurrent minor aphthous ulceration: a randomized blind controlled parallel double-center clinical trial
  3. Efficacy of alum for treatment of recurrent aphthous stomatitis
  4. Evaluation of the therapeutic effects of Aloe vera gel on minor recurrent aphthous stomatitis
  5. Oil pulling for maintaining oral hygiene – A review
  6. Chamomile: A herbal medicine of the past with bright future
  7. Mercury intoxication presenting with tics
  8. Effectiveness of Vitamin B12 in Treating Recurrent Aphthous Stomatitis: A Randomized Double-Blind Placebo-Controlled Trial
  9. The Effectiveness of Vitamin B12 for Relieving Pain in Aphthous Ulcers: A Randomized Double-blind Placebo-controlled Trial
  10. A new therapeutic candidate for oral aphthous ulcer: Allicin
  11. Effect of Herbal Echinacea on Recurrent Minor Oral Aphthous Ulcer
  12. Canker sores (mouth ulcers): Overview

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Monomita holds a master’s degree in journalism and mass communication. Her passion for and understanding of all things related to skin, hair, and beauty propelled her to pursue a career in writing. She wants to travel the world and taste all kinds of food, preferably with a cat as her companion. She is a trained film director, and her eclectic taste in cinema ranges from anime to horror movies.