Mouth Ulcers (Aphthous Stomatitis)

Some people with inflammatory bowel disease (IBD) may experience various extra-intestinal symptoms along with the symptoms in their gastrointestinal tract. These can include skin irritation, eye problems, and joint pains, among other things. One of these extra-intestinal conditions is aphthous stomatitis, or ulcers in the mouth. For some with IBD, mouth ulcers might be one of the first signs that the IBD may be flaring up again.

Canker sores, or aphthous ulcers, are the lesions caused by aphthous stomatitis. They may seem like a fairly benign, limited condition, but in the presence of so many other problems that occur with IBD they can be upsetting and painful. Fortunately, they are usually harmless and treatment is aimed at reducing discomfort.

Aphthous stomatitis is not believed to be contagious and cannot be spread to other people.

There are many things that can be done to make mouth ulcers less painful. For people with IBD, getting the inflammation caused by the IBD under control will usually help in controlling the ulcers and allowing them to heal.

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Aphthous ulceration
 DermNet / CC BY-NC-ND

Symptoms of Mouth Ulcers

Aphthous ulcers are shallow ulcers in the mucosa (lining) of the mouth. They may appear anywhere in the mouth but are frequently found on the inside of the lower lip or cheeks, or on the sides or base of the tongue. They may last from 1 to 2 weeks to months. The ulcers may appear whitish or yellow with a red base, with a grayish layer that develops when they begin to heal. They may also be described as looking like a blister.

Causes of Mouth Ulcers

It is not known why aphthous stomatitis may appear in some people with IBD. Some theories include stress, bacterial infection, or trauma. There could be a link between the development of severe aphthous stomatitis and having a weakened immune system. Some other potential causes of aphthous stomatitis also include deficiencies of various vitamins and minerals (though these are uncommon).

Diagnosis of Mouth Ulcers

A case of aphthous stomatitis that is not very troublesome or painful does not necessarily require a specific visit to a physician. However, it should be discussed at the next visit to the gastroenterologist who is treating the IBD.

If the ulcers become large, very painful, or do not heal, a dentist or physician should be consulted. A gastroenterologist can determine if the ulcers are in fact aphthous stomatitis, in most cases simply by their appearance and if further testing or any treatment is needed.

Mouth ulcers can be caused by other conditions (such as contact dermatitis, herpes infection, hand-foot-and-mouth disease, and lupus) that may need treatment so they should always be seen by a physician for a diagnosis.

If the ulcers do appear troublesome, the physician may order tests such as a complete blood cell count; erythrocyte sedimentation rate; and iron, folate, and B-12 levels. A culture or biopsy of the lesions may also be taken.

Treating Mouth Ulcers

Mild cases of aphthous stomatitis may not require any treatment as the ulcers will heal on their own. Topical anesthetics such as lidocaine are frequently prescribed for local pain relief. Troublesome ulcers may be treated with a topical corticosteroid in a paste, cream, spray, or rinse.

A specific treatment for aphthous stomatitis, amlexanox, is occasionally prescribed for topical use as well, with published studies showing good effectiveness. Mouth rinses that reduce the amount of bacteria in the mouth may also be used. Cases of aphthous stomatitis that are related to a serious underlying condition such as HIV infection may be treated with oral medication.

If the ulcers are irritated by certain foods, there may need to be a change in diet. Soft, bland, non-acidic foods (without spices or salt) may lessen irritation. Sucking on ice chips may relieve some pain.

Other treatments, such as applying milk of magnesia to the sores or rinsing with salt water, diluted hydrogen peroxide, or Benadryl (diphenhydramine) may be helpful in some cases. Painkillers are also sometimes used, but remember that NSAIDs may cause a flare-up of IBD in some people.

Because aphthous stomatitis may also be worsened by trauma, it is important to take care to not bite or injure the inside of the mouth. Any dental problems (jagged teeth, ill-fitting appliances) that may be causing or contributing to the ulcers should be addressed by a dentist.

In cases of aphthous stomatitis that are due to a flare-up of IBD, the ulcers typically resolve when the flare-up is under control.

2 Sources
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  1. Lankarani KB, Sivandzadeh GR, Hassanpour S. Oral manifestation in inflammatory bowel disease: a reviewWorld J Gastroenterol. 2013;19(46):8571–8579. doi:10.3748/wjg.v19.i46.8571

  2. Pereira MS, Munerato MC. Oral Manifestations of Inflammatory Bowel Diseases: Two Case ReportsClin Med Res. 2016;14(1):46–52. doi:10.3121/cmr.2015.1307

By Amber J. Tresca
Amber J. Tresca is a freelance writer and speaker who covers digestive conditions, including IBD. She was diagnosed with ulcerative colitis at age 16.