Canker Sores

Canker sores are blisters that develop in the mouth and result in pain and discomfort. They can be of two types, simple canker sores and complex canker sores. Simple canker sores persist for about a week and usually affect individuals between the ages of 10 and 20 years. These sores may develop up to 3 to 4 times in a year. Complex canker sores mostly affect individuals who have had them before. They are less common than simple canker sores. Canker sores are often confused with cold sores. While canker sores generally develop inside the mouth, cold sores occur outside the mouth.

Canker Sores Picture

Symptoms of Canker Sores

Canker sores appear as reddish round ulcers with a whitish center. They usually form beneath the tongue, on the insides of the cheeks and on the gums. You can tell when canker sores are about to develop due to the tingling sensation that occurs 2 to 3 days earlier. Canker Sores symptoms include:

  • A tingling or burning sensation in the area where the sores are about to develop
  • Round or oval shaped ulcers that are red around the edges and white or yellow in the center
  • Fever
  • Swollen lymph glands
  • Sluggishness

It is advisable to see a doctor in case any of the following symptoms occur:

  • Large sores
  • Recurring canker sores that develop before the earlier ones have healed
  • Sores that persist for more than three weeks
  • Sores that develop on the lips
  • Severe pain
  • Difficulty in moving the mouth while eating or drinking
  • High fever

Sometimes the sharp edges of a tooth or poorly fitted dental fixtures may contribute to the sores. In such cases, it is advisable to consult your dentist.

Causes of Canker Sores

The exact causes of canker sores are not clearly understood. There could be a variety of factors that play a role in an outbreak of these sores. Some common causes of canker sores include:

  • Allergies to certain foods
  • Allergic reaction to the bacteria present in the mouth
  • Minor injuries to the mouth due to sharp teeth, dental fixtures, rough brushing, accidental bites and the intake of acidic or pungent foods
  • Sensitivity to certain foods such as cheese, eggs, nuts and acidic fruits
  • Deficiencies of zinc, iron, folic acid and vitamin B-12
  • Infection due to certain types of bacteria
  • Celiac disease, a condition that affects the intestines and occurs due to intolerance to gluten contained in grains
  • Bowel disorders such as ulcerative colitis
  • Autoimmune disorders which cause the white blood cells to attack the cells of the mouth
  • Diseases that weaken the immune system such as HIV
  • Stress
  • Use of toothpastes and other oral hygiene products that contain harsh substances

Remedies for Canker Sores

To alleviate the pain and facilitate proper healing, make sure you take certain precautions and make a few changes to your diet and lifestyle. You can try using some of these home remedies and other tips to help alleviate the pain and hasten the healing process:

  • Baking soda constitutes one of the most common and popularly used home remedies for canker sores in mouth. Prepare a paste of baking soda and a little bit of water and apply to the sores. You can also add some baking soda to warm water and rinse your mouth with the solution.
  • Avoid eating acidic or spicy foods that will simply increase the pain and discomfort.
  • Apply ice on the canker sores to soothe the pain and reduce inflammation. You can effectively stop canker sores from developing if you start applying ice regularly, as soon as you experience the initial symptoms.
  • Be gentle while brushing your teeth and use toothpastes that do not contain foaming agents.
  • Plum juice serves as a beneficial canker sore natural treatment. Take a couple of tablespoons of plum juice and rinse the mouth with it for a few minutes. You can also dip a cotton ball in plum juice and hold it against the affected areas.
  • You can apply alum on the sores to relieve pain. Alum may cause slight burning for a few minutes. You can use alum twice daily and then rinse with water.
  • Place a wet tea bag against canker sores to reduce inflammation. The tannic acid contained in tea helps to reduce pain, making it one of the most effective natural remedies for canker sores.
  • Salt water is extremely beneficial in curing canker sores. Add a tablespoon of salt to warm water and rinse the mouth with it at regular intervals during the day. Salt helps to dry out the sores and enables proper healing.
  • Place a piece of raw onion against the affected area to promote healing.
  • Extract the oil from a vitamin E capsule and apply directly to the sores.
  • Rinse your mouth with aloe vera juice three to four times a day. Aloe has anti-inflammatory properties and thus helps to ease pain. It is also effective in destroying bacteria.
  • Many individuals find relief from canker sores after using aspirin. Place an uncoated tablet on the affected area until it dissolves. The sores should start subsiding almost immediately.
  • Hydrogen peroxide can be used as a mouth wash. It may foam inside the mouth and it should not be swallowed. But it does prove to be effective in destroying germs. If you are unable to use undiluted hydrogen peroxide, you can mix it with water.
  • Add a few drops of grapefruit seed extract to a glass of water and use to rinse the mouth once daily. Grapefruit seeds help to reduce infection by working as a natural disinfectant.
  • Myrrh contains tannin which serves to curb the growth of germs. You can use myrrh in the form of capsules. You can also add about 200mg of myrrh extract to warm water and wash the mouth with it thrice daily.
  • Add three tablespoons of dried chamomile flowers to boiling water. Allow it to cool for ten minutes, strain and then sip throughout the day. This is known to help in curing canker sores.
  • Add a couple of teaspoons of calendula in a cup and pour boiling water over it. Steep for a few minutes, filter and then use to gargle. You can do this three to four times daily.
  • Marjoram is also known to be beneficial in treating canker sores. Pour boiling water over two tablespoons of marjoram. Cover and keep for ten minutes and then use to rinse the mouth.

Keep in mind that most home remedies are not supported by adequate scientific research and their efficacy remains questionable.

Diet for Canker sores

With a healthy and balanced diet, you can protect yourself against canker sores. Some helpful dietary tips include:

  • Eat more yogurt. There are active cultures contained in yogurt that help to encourage healing of sores. It also minimizes the risk of further occurrences of canker sores.
  • Increase your intake of foods rich in B vitamins. Foods such as whole grains and green, leafy vegetables are high in the B complex vitamins and are effective in preventing canker sore outbreaks. You can also consume nutritional yeast, which is available in health food shops. This yeast may be added to foods or liquids.
  • Kiwi fruit is known to help in healing canker sores. This could be because of the bioflavonoids and vitamin C that the fruits contain.
  • Sauerkraut contains probiotics that are beneficial bacteria or yeast. You can buy fresh sauerkraut juice from the supermarket and use it to rinse the mouth.
  • Other good foods to eat with canker sores include soft cooked grains, steamed vegetables, foods that are easy to digest and carrot juice.
  • Avoid eating foods that may trigger allergic reactions. Many individuals suffer from canker sores because of gluten insensitivity. Restrict your intake of citrus fruits, spices and caffeinated beverages. Also reduce your consumption of foods such as dairy products, animal protein sources, salty foods, sweets and oily foods.

Suggestions for Canker Sores

In many cases stress seems to trigger canker sores. If you work in a highly stressful environment it may be a good idea to slow down on those career goals and try out some relaxation techniques such as meditation, aromatherapy or deep breathing exercises.


  1. Reuter J, Jocher A, Stump J, Grossjohann B, Franke G, Schempp CM. Investigation of the anti-inflammatory potential of Aloe vera gel (97.5%) in the ultraviolet erythema test. Skin Pharmacol Physiol. 2008;21(2):106-10. doi: 10.1159/000114871. Epub 2008 Feb 5. PubMed PMID: 18253066.

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20 Canker Sores remedies suggested by our users
suggested by Jay on Saturday, January 10, 2009

Many foods are listed to avoid when it comes to canker sores. Chocolate, nuts, oranges etc. These foods have one thing in common. We eat them with our hands. I have discovered that by not putting my fingers in my mouth (nail biting, eating etc) and I don't get them anymore. I used to get them all of the time. So, stop letting your fingers get into your mouth. Be careful when eating popcorn, fruit etc!

Baking soda
suggested by [unspecified] on Wednesday, June 11, 2008

Just put baking soda (1 tsp) in 1/2a cup of water. It'll relieve the pain because the carbohydrates in the baking soda naturally relieve the canker of pain and cleanses it of bacteria that causes the canker in the first place. It also kind of relieves u of tooth pains from braces, root canal, etc.

Canker Sore Remedy
suggested by Anne on Monday, June 2, 2008

When I was a kid my Mom told me to put a little Cream of Tarter powder on the end of a Q-tip and then put that on the canker sore. It hurts a lot, but the sore is gone the next day.

Green Pepper
suggested by Bill on Wednesday, May 28, 2008

I was really surprised the no one has suggested eating a little raw green pepper. This has been my cure for years and it has never failed.

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