Canker sore

Overview

Canker sores are small sores that form on the soft tissues inside your mouth. They may appear on the inside of your cheeks or lips. They also can appear under or on your tongue, at the base of your gums, or on the soft roof of your mouth, called the palate. Canker sores usually have a white or yellow center with a red border. They can be painful and may make it hard to eat and talk.

Canker sores, also called aphthous ulcers, are not the same as cold sores. Canker sores do not form on the lips and are not caused by a herpes virus infection. They cannot be spread to other people.

Most canker sores go away on their own in 1 to 2 weeks.

Causes

The exact cause of canker sores isn't clear. Experts believe that several factors may play a role. Possible triggers for canker sores include:

• Food sensitivities or allergies, such as to chocolate, eggs, nuts, and spicy or acidic foods.
• Certain toothpastes and mouth rinses that have sodium lauryl sulfate, a foaming agent.
• An injury to your mouth from dental work, brushing too hard, biting your cheek or playing sports.
• Some medicines, including certain medicines used to treat heart conditions and osteoporosis and nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil, Motrin IB, others) and naproxen sodium (Aleve, Anaprox DS, others).
• Hormonal changes during menstruation.
• Emotional stress.

Canker sores also may occur because of certain medical conditions, such as:

• Celiac disease, which is an autoimmune condition where the immune system reacts to gluten, sometimes causing damage to the small intestine. Gluten is a protein found in foods that have wheat, barley or rye.
• Low levels of vitamin B-12, zinc, folate or iron in the body that can happen from not eating a balanced diet.
• Inflammatory bowel diseases, such as Crohn's disease and ulcerative colitis.
• Behcet disease, which is a rare condition that causes blood vessel inflammation throughout the body and mouth sores.
• A change in the immune system that causes the body to attack healthy cells in the mouth instead of germs such as viruses and bacteria.
• HIV/AIDS, which is a condition that damages the immune system so that the body is less able to fight infection and disease.

Canker sores are not caused by a herpes virus infection.

Prevention

You may be able to lessen how often canker sores occur. These tips may help:

• Stay away from foods that irritate your mouth. These may include nuts, certain spices, salty foods and acidic fruits, such as pineapple, grapefruit and oranges. Don't eat foods to which you're sensitive or allergic.
• Choose healthy foods. Eat a balanced diet. Include a variety of fruits, vegetables and whole grains.
• Follow good mouth care habits. Regular brushing after meals and flossing once a day can keep your mouth clean and free of foods that might trigger a sore. Use a soft toothbrush to keep from irritating your mouth. Don't use toothpastes and mouth rinses that have sodium lauryl sulfate.
• Protect your mouth. See your dentist if you have sharp tooth surfaces or dental appliances that seem to trigger the sores. Ask about orthodontic waxes to cover sharp edges. Try a mouthguard during sports activities.
• Lower your stress. If your canker sores seem to be linked to stress, practice ways to lower your stress, such as meditation and guided imagery.

Treatment

Treatment usually isn't needed for minor canker sores. These tend to heal on their own in 1 to 2 weeks. You may need treatment if sores are large, do not heal or are very painful. Treatment may include mouth rinses, topical products, oral medicine, cautery of the sores or nutritional supplements. Or treatment for related health conditions may be needed.

Mouth rinses

If you have several canker sores, your healthcare professional may prescribe a mouth rinse that has the steroid dexamethasone (dek-suh-METH-uh-sown). This can lessen pain and swelling. A rinse that has lidocaine, a numbing medicine, can lessen pain.

Topical products

Prescription products and products you can buy without a prescription may help ease pain and speed healing. These include pastes, creams, gels or liquids that you put on the canker sore as soon as it appears.

Common active ingredients in topical products include:

• Benzocaine (Anbesol, Kank-A, Zilactin-B).
• Fluocinonide (Vanos).
• Hydrogen peroxide (Orajel Antiseptic Mouth Sore Rinse, Peroxyl Mouth Sore Rinse).

There are many other topical products for canker sores, including those without active ingredients. Ask your healthcare professional or dentist for advice on which may work best for you.

Oral medicines

Oral medicines may be used when canker sores are severe or don't heal with topical treatments. These may include:

• Medicines not intended specifically for canker sore treatment. Examples include colchicine used to treat gout and the intestinal ulcer treatment sucralfate (Carafate), a coating agent.
• Oral steroid medicines when severe canker sores don't heal with other treatments. Because of the potential for serious side effects, they're usually not the first treatment choice.

Cautery of sores

During cautery, tissue is burned away to get rid of the canker sore. Chemical cautery uses a substance placed on the canker sore. Low-level laser therapy also is an option. Cautery is used for more-painful or more-severe canker sores, especially to lessen pain.

Nutritional supplements

If testing shows that you have low levels of important nutrients, such as folate, vitamin B-6, vitamin B-12, or zinc, your healthcare professional may suggest a nutritional supplement.

Related health conditions

If a medical condition is causing your canker sores, your healthcare professional can treat the health condition.

Preparing for an appointment

Your healthcare professional or dentist diagnoses a canker sore based on your symptoms, medical history and how the sore looks. Here's some information to help you get ready for your appointment.

Before your appointment make a list of:

• Your symptoms, including when they started and if they've changed or worsened over time.
• All medicines you're taking, including vitamins, herbs and other supplements, and the doses.
• Other health conditions you have, if any.
• Key personal information, including any recent changes or stress in your life.
• Questions to ask your healthcare professional or dentist.

Some basic questions to ask:

• Do I have a canker sore? If not, what else could it be?
• What factors may be causing the sore?
• Do I need any tests?
• What treatment do you recommend, if any?
• What can I do to lessen pain? Is there anything I can do to speed up healing?
• How soon do you think my symptoms will get better?
• Is there anything I can do to keep from having another canker sore?

Feel free to ask other questions during your appointment.

What to expect from your healthcare professional or dentist

You may be asked:

• What are your symptoms?
• When did you first notice these symptoms?
• How severe is your pain?
• Have you had sores like this in the past? If so, have you noticed if anything seems to trigger them?
• Have you been treated for sores like this in the past? If so, what treatment worked best?

You also may be asked about possible triggers:

• Have you had any recent dental work?
• Have you recently had a lot of stress or major life changes?
• What is your typical daily diet?
• Have you been diagnosed with any other medical conditions?
• What medicines do you take?
• Do other family members also have canker sores?

Be ready to answer questions so that you'll have time to talk about what's most important to you.