Canker Sores

Canker sores are small, painful mouth ulcers that develop most often in the soft fold of tissue where the inner cheeks meet the gums. Other common sites include the soft palate, tongue, and floor of the mouth; it is not unusual for two or three to appear at a time, even 10 or more in some cases. They start as small red areas and within a day or two, each center forms a yellow or white crater. Ranging in size from an one eighth inch to one-half inch or more across, they can be painful enough to interfere with speaking and eating the first two or three days. Some people also develop a low grade fever, swollen lymph nodes, and feelings of general malaise. Their specific cause is unknown, but canker sores are frequently linked to fatigue, stress, poor diet, or debilitated physical condition due to another ill ness. People with AIDS or certain types of cancer often develop the sores, possibly due to a weakened immune system. In contrast, some researchers believe that the sores are more likely to develop when the body’s immune system attacks healthy tissue. Another possible cause is irritation from overly vigorous brushing of the teeth, eating certain foods, dental fillings that scrape the mouth, and poorly fitted dentures. In women, canker sores often appear just prior to menstruation. Recurring attacks are common, but most canker sores heal within two weeks and leave no scars.

Diagnostic Studies And Procedures

The sores are readily diagnosed by a visual examination. In some cases, a laboratory culture may be needed to distinguish them from those of herpes, and to rule out the presence of a secondary bacterial infection.

Medical Treatments

Medical care is not usually necessary unless the condition persists or recurs frequently. In such cases, a mouthwash with tetracycline may be prescribed to relieve pain, especially if a secondary infection is present. In severe cases, a doctor may prescribe steroid medication to be used both as a mouthwash and in tablet form. Other prescription products are anesthetic mouthwashes to make eating more comfortable, and a paste that is applied to the ulcer to relieve pain and promote healing.

Alternative Therapies


Lemon oil applied during a facial massage is recommended for treating canker sores.

Herbal Medicine

The tannic acid in tea is astringent, helping to dry up canker sores and bring relief from pain. Dip a regular teabag into boiling water, squeeze out most of the water, allow it to cool, then apply it to the canker sore for three minutes. Repeat as needed until the sore disappears. Herbalists also suggest rinsing the mouth with a rose water decoction, made by simmering rose petals in a pint of water. Other popular herbal remedies include rinses made from raspberry leaf, burdock, sage, or red clover decoctions. Tincture of myrrh may be applied directly to the sore, but caution is recommended, because it can damage delicate mouth tissue.

Naturopathy and Nutrition Therapy

Until the sores heal, it’s best to eat soothing, cool foods. Milk, gelatin, ice cream, puddings, and custard usually are well tolerated. Yogurt with active lactobacillus acidophilus cultures is both soothing and reportedly speeds healing. In fact, many naturopaths advocate acidophilus pills, starting with two tablets per meal, decreasing the dosage as the condition clears up. Onions, either raw or cooked, are recommended for their high sulfur content. Avoid chocolate, citrus fruits, acidic foods, and salty or spicy foods, which are likely to irritate the ulcers. If you suffer from recurrent sores, have a nutritionist analyze your diet to make sure it provides adequate folic acid, iron, zinc, and vitamin B 12 . A limited number of studies have shown a link between canker sores and deficiencies of these nutrients.

Yoga and Meditation

Because canker sores at times appear to be related to stress, these and other relaxation techniques, including breathing exercises, can be a helpful aspect of both treatment and prevention.

Self Treatment

Most canker sores will clear up within 7 to 10 days. In the meantime, to relieve pain, try an over the counter anesthetic gel or liquid, applying it directly to the ulcer. A styptic pencil, such as those used by barbers to stop bleeding from minor nicks, numbs the nerve endings and provides temporary relief. Aspirin, acetaminophen, or ibuprofen can also help with pain. Rinse your mouth several times a day with a mild solution of saltwater( ½ teaspoon of salt in I cup of warm water), and clean the sores frequently with a cotton swab dipped in a solution of one part 3-percent hydrogen peroxide to four parts water. To clean teeth, use a soft toothbrush and baking soda, which is less irritating than toothpaste. See your dentist if you think the sores are being caused by braces, dentures, or a rough tooth.

Other Causes of Mouth Ulcers

A herpes simplex infection causes fever blisters or cold sores that resemble canker sores. If you have previously had a herpes infection, the sores may recur at the same time canker sores appear because they seem to share precipitating factors. Also, oral thrush, a yeast infection, shows up as white patches in the mouth, which can result in small painful ulcers. Smoking promotes mouth sores in some people, but it more commonly causes leukoplakia, thick whitish patches that often evolve into cancer.