Canker Sores Types, Causes, Treatment and Home Remedies

Canker sores are at best a short-term, unpleasant nuisance, and at worst an extremely painful condition which can make eating, drinking and even talking particularly uncomfortable for a period of six weeks or more. The more you know about exactly what canker sores are, and what causes them, the better your chances are of treating them when they occur and preventing them in the future.

Canker Sore

Exact definition of canker sores

Canker sores are lesions – raised and discolored areas – appearing on the soft parts of the inside of the mouth. They can appear as canker sores on the tongue, canker sores in the throat, inside cheeks and lips or at the bottom of the gums. They vary in size from tiny pinpricks to large, deep, irregular-shaped sores, and stay around for between one and six weeks. The larger sores have a central area which is white or yellow, while the edges are red in color. The medical term for a canker sore is ‘aphthous ulcer’, and a person with canker sores is suffering from ‘apthous stomatitis’.

Types of canker sores

There are three main types of canker sores:

  • Small oval sores which go away after two weeks at most and leave no scars. These are the most common type of canker sores.
  • Herpetiform canker sores, which are less common and usually afflict older people. They are individually the size of a pinpoint but they can cluster together in large groups. Once again they usually disappear within two weeks without causing scarring.
  • Large, deep canker sores with uneven outside edges. They are not as common as the smaller type of sore, and can remain in evidence for around six weeks, leaving behind scars.

Canker sores should not be confused with cold sores, which appear on the outside of the lips and are caused by herpes virus infections. Cold sores are contagious and can be passed from person to person by skin contact or by sharing cutlery, glasses and cups. However, canker sores are not contagious, so kissing or getting up close and personal is not a problem when you or someone you love has canker sores.

Canker sores causes

The jury is still out on exactly what causes canker sores, but scientists and doctors have made some educated guesses. It seems likely that they may be caused by a combination of factors present in the lifestyle of an individual, rather than being attributable to a single source.

  • ‘Scrubbing’ teeth and gums. People who brush their teeth too vigorously may be unwittingly laying themselves open to canker sores. Aim for a happy medium involving good dental hygiene without too much pressure or scrubbing.
  • Mouth wounds. Injuries to the inside of the mouth may cause canker sores. These wounds may be the result of wearing braces or dentures, other dental treatment, sports collisions, or even accidentally biting some of the fleshy tissue inside your own mouth or jabbing it with the end of a toothbrush.
  • Reaction to food. Canker sores may also be set off by consuming very spicy foods and acidic fruits such as pineapples, or by allergic reactions to other items including coffee, chocolate, nuts, some cheeses, eggs, nuts and strawberries.
  • Reaction to bacteria. It’s possible that some bacteria naturally found in the mouth, including the very common heliobacter pylori, may cause an allergic reaction in some individuals.
  • Sodium lauryl sulfate. This chemical ingredient is found in some brands of mouthwash and toothpaste. It may activate canker sores and it has been linked to cancer.
  • Dietary deficiencies. If your regular diet has insufficient quantities of iron and zinc (clams, mussels, oysters, liver, seeds, nuts, beef, spinach), folic acid (green vegetables and citrus fruits) or vitamin B-12 (shellfish, liver, fish), you could be increasing your risk of developing canker sores.
  • Canker sore outbreaks may be one of the ways your body reacts to a stressful job, impending exams or upsets in your personal life.
  • Hormonal changes occurring in a woman’s body during her monthly period may activate canker sores, and women in general are more likely to have canker sores than men.
  • Canker sores in the mouth are a symptom of some diseases, such as intestinal and bowel diseases, and immune system problems including HIV/AIDS.
  • It appears that a predisposition to canker sores may be inherited, either through genes or because families tend to share lifestyle factors such as their diet.

Canker sores treatment

All but the most severe canker sores tend to disappear without any specific treatment after a couple of weeks. However, it is possible to treat acute outbreaks, and reduce the associated pain, with a mouthwash containing a steroid called dexamethasone. This must be prescribed by a doctor, and may be used in conjunction with a healing paste applied directly onto the sores.

In really serious cases, a doctor may prescribe a course of steroid medication, or dietary supplements to counteract the shortfalls in iron, zinc, folic acid or vitamin B-12 discussed above. Alternatively, the sores may be cauterized by applying chemicals to seal them.

Canker sores home remedies

It isn’t always necessary to see a doctor in order to get some relief from canker sores. The ingredients you need to treat them may be already sitting at home in your kitchen or medicine cabinet, and they can be combined in a variety of ways in order to reduce pain and swelling.

  • Milk of magnesia can provide some respite from pain. Apply a small amount directly onto the sores several times each day.
  • Baking soda rinse. Mix a teaspoon of baking soda in a cup of warm water and use this as a mouthwash. Alternatively, make a paste of baking soda and a few drops of water, and apply directly onto the sores.
  • Salt water rinse. Use the same method as the baking soda rinse, i.e. one teaspoon per cup of warm water.
  • Benadryl rinse. There are three common medications you may already have at home: Benadryl (for treating allergies), Kaopectate (a diarrhea cure) and Maalox (to relieve indigestion and heartburn). Equal parts of Benadryl and either Kaopectate or Maalox may be used as a mouth rinse, but do not swallow them.
  • Aloe vera juice. Rinsing your mouth several times a day with aloe juice can be effective in speeding up the process of healing, but swallowing too much should be avoided since it can cause diarrhea.
  • Hydrogen peroxide rinse. Use a 3% hydrogen peroxide solution mixed with an equal quantity of warm water. Most definitely do not swallow the rinse, and do not use it for prolonged periods.
  • Chipped ice from your freezer can be effective in numbing the pain and reducing swelling. Let it gradually dissolve in your mouth.
  • Benzococaine, found in oral gels (e.g. Orajel, Anbesol, Orabase) that you can buy over the counter at the pharmacy, helps to reduce the discomfort of canker sores.
  • Probiotic or acidophilus. This is a substance found in natural, unflavored yogurt, usually consumed as an aid to digestion or to soothe stomach cramps. Look for the word ‘probiotic’ on the label, and just make the live culture yogurt a part of your regular diet to increase your resistance to canker sores. Acidophilus can also be taken in the form of tablets bought from your local pharmacy.
  • Papaya or kiwi fruit and juice. Eating either of these fruits, or drinking their juice, will be beneficial for canker sore sufferers. They are quite delicious and good for your general health at the same time, so why not add both of them to your regular diet? For best results, just hold the fruit’s flesh or juice in your mouth before you swallow, so that it comes into contact with the sores for a little while.
  • Peppermint and eucalyptus essential oil spray. You can make this spray at home and use it whenever the discomfort of canker sores makes you crave some temporary respite from pain. Just combine 10 drops of peppermint oil, 8 drops of eucalyptus oil and 2 tablespoons of olive or grape seed oil. Put the mixture in a glass or plastic mister spray bottle, shake well, and spray it on your sores whenever you want to numb the pain and cool down your mouth. Both of these oils also act as an anti-inflammatory and anti-bacterial.
  • Tea bags. This remedy could not be easier. Every time you have a cup of tea, press the used tea bag (once it has cooled) against the sores, and keep it there as long as possible, up to about 15 minutes. The tannic acid in the tea bag works as an astringent to promote healing and reduce swelling. Chamomile tea is said to be especially beneficial, but if you don’t like the taste, just soak the tea bag in water before applying it to your sores.
  • Sage rinse or pulp. Herbal remedies have been used for centuries to promote healing, and have the benefits of being both natural and safe. The herb sage has been found to be a helpful treatment for canker sores, either as a mouth rinse or as a paste. For the mouthwash, boil 2 teaspoons of dried sage in about 6 ounces of water, or let a handful of fresh sage leaves infuse in water overnight. If using fresh sage, the leaves (after being removed from the water to leave behind the mouth rinse) can be squashed into a pulp and also applied to the sores.
  • Coconut oil or organic honey can be gently applied to the sores with the fingertip or a cotton swab and left in place. They have soothing and healing properties and may be used several times a day.
  • Clove oil contains a natural form of eugenol, a substance still used by dentists for pain relief. Soak a cotton ball in a mixture of 5 drops of clove essential oil and half a teaspoon of olive oil. Then put the cotton ball against the canker sore and hold in place for a few minutes to numb the pain.

Lifestyle changes to reduce canker sore outbreaks

Good oral hygiene is a must for anyone wishing to avoid or reduce the occurrence of canker sores. This means brushing teeth after each meal, and flossing teeth once daily. However, since over-enthusiastic brushing of teeth is believed to be a cause of some canker sores, it makes sense to use a gentler cleaning motion and a soft brush. Only buy toothbrushes labeled as ‘soft’, and switch to a toothpaste that does not contain a foaming agent or one that is specially formulated to prevent or relieve canker sores.

If you wear braces or dentures, you can make a wax coating to prevent canker sore-inducing abrasions inside your mouth. Simply combine a tablespoon of melted beeswax and two teaspoons of coconut oil and press lumps of the thick, cooled mixture onto the edges of your dentures or braces to reduce friction.

Similarly, if you are predisposed to canker sores, avoid foods which are acidic, spicy or salty, or have sharp edges (like a taco shell, for example), since any of these may trigger outbreaks or aggravate existing sores. At the same time, take affirmative action to improve your diet by introducing plenty of the foods already listed that are rich in iron, zinc, folic acid and vitamin B-12.

If you feel that stress may be a factor in causing your canker sores, ask your doctor to recommend stress reduction techniques that can be learned, such as meditation.

Your doctor should always be consulted if your canker sores keep appearing again and again, or are causing so much pain and distress that they are interfering with your ability to enjoy life. They could be a symptom of a more worrying disease that needs to be medically treated. So by all means try home remedies for minor occurrences of canker sores, and adapt your lifestyle, especially your diet, in order to reduce the likelihood of getting them, but do seek medical advice if these DIY canker sore preparations and adaptations do not work for you.