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A mouth ulcer is a small sore in the mucous membranes inside the mouth

What is going on in the body?

The mouth is sensitive to many irritations. Problems in other parts of the body can also cause sores in the mouth. Although most mouth sores will go away by themselves and are of little concern, some are much more serious.

What are the signs and symptoms of the condition?

Mouth ulcers are generally yellow or gray in color and vary in size. Other signs and symptoms may include the following:

• difficulty chewing
• mild fever
• pain when brushing or using mouthwash
• soreness
• swelling around the ulcer

What are the causes and risks of the condition?

• accidental cheek, lip, or tongue biting
• accidental damage from tooth brushing
• allergic reaction to medications
• burns from food or drink that is too hot
• burns or irritations from medications, such as aspirin
• cancer of the mouth or lips
• chemotherapy or radiation therapy
• denture sores
• electrical burns
• food allergy
• HIV, the virus that causes AIDS
• food allergy
• an impacted tooth
• irritation from a dental procedure
• irritation from orthodontic appliances
• localized irritation from a disease, such as Parkinson's disease
• medications that cause mouth dryness, including antihistamines such as diphenhydramine
• a new tooth coming in, known as a tooth eruption
• reactions to tobacco products
• serious medical illnesses that weaken the person, such as cancer
• some sexually transmitted infections, such as gonorrhea or genital herpes
• viral disease, such as oral herpes

Women are more prone to mouth ulcers than men are, especially during pregnancy or right before a menstrual period.

What can be done to prevent the condition?

• Avoid food and drinks that are too hot.
• Avoid foods, medications, and other substances that trigger allergic reactions.
• Drink plenty of liquids when taking medications that cause mouth dryness.
• Eat a balanced diet, following the Food Guide Pyramid.
• Follow good oral hygiene, including regular tooth brushing and flossing.
• Practice safer sex to avoid sexually transmitted diseases
• Seek prompt treatment for denture problems, impacted teeth, or irritating orthodontic appliances.
• Quit smoking.

How is the condition diagnosed?

Since many mouth sores look alike, diagnosis is best done by a health professional. Any ulcer of the mouth or lips that lasts longer than a week should be seen by a healthcare professional.

What are the long-term effects of the condition?

Mouth ulcers rarely cause long-term effects, unless they become seriously infected.

What are the risks to others?

Some mouth ulcers are contagious through direct contact, while others are not.

What are the treatments for the condition?

• Clean the area gently with a very soft brush and mild (1-1/2%) hydrogen peroxide or a warm salt water solution made by adding 1/2 teaspoon salt to a full glass of warm water).
• Do not use any medications before checking with a health professional.
• Keep the area clean and clear of food scraps.
• See a healthcare provider if the ulcer lasts more than a week.

The healthcare provider may prescribe a liquid paint, mouthwash, gel, or rinse to treat the mouth ulcer.

What are the side effects of the treatments?

Rarely, medications used to treat mouth ulcers may cause an allergic reaction.

What happens after treatment for the condition?

Mouth ulcers usually go away on their own or with treatment. If the underlying cause of the ulcers is not treated, they may recur. A person with recurring mouth ulcers should see a healthcare professional for further diagnosis.

How is the condition monitored?

Any new or worsening symptoms should be reported to the healthcare provider.