Cold Sores and Cankers

There are many causes of sores in the mouth and on the lips. These may include viral infections, bacterial infections, allergic reactions, irritants, nutritional deficiencies and trauma. Mouth sores can be painful, unsightly and slow to heal. Two of the most common mouth sores are cold sores and cankers.

Cold Sores

Cold sores (herpes simplex), also called fever blisters, are fluid-filled red blisters that occur outside the mouth, on or around the lips. They can also occur around the nose and on the cheeks.

Causes

Cold sores are caused by the herpes simplex virus (HSV), usually type I. About eight out of every 10 people is infected with HSV-1. The virus lies dormant in nerve cells. It becomes active and causes a cold sore when the immune system is occupied fighting an illness or when the body is stressed by other situations.  

Cold sores are contagious. You can get them from skin-to-skin contact, such as kissing, or from sharing eating utensils or towels with someone who has a cold sore. Certain triggers may cause repeated outbreaks:

• Physical or emotional stress

• Menstruation

• Cold or fever

• Upset stomach

• Excessive exposure to the sun

• Excessive alcohol consumption

• Use of medications that suppress the immune system

HSV-1 can be dangerous to newborn babies, elderly adults and people who have a chronic disease, have weakened immune systems (HIV/AIDS) or are taking immunosuppresant medications. These people should avoid contact with anyone who has symptoms of a cold sore.

HSV-1 can be transmitted to other parts of the body. An HSV-1 infection of the finger is called "herpetic whitlow." HSV-1 can cause blindness if eyes become infected. It can infect the genital area. HSV-2, the virus that usually causes genital herpes, can also cause infections on the face.

Symptoms

A cold sore frequently begins as a burning or tingling sensation at the point where the sore will appear. Within a few hours painful, clear blisters appear at the site of the outbreak. The sore continues to enlarge for several hours. Within a day or two, the blisters break and a crust forms. The crust darkens and, after seven to 10 days falls off, revealing a slightly pinkish healed area. 

Treatment

There is no cure that will eliminate the HSV-1 virus from the body. Attempts to prevent cold sores don’t always work. Most cold sores will clear up on their own in seven to 10 days, but there is discomfort and a certain degree of social embarrassment with having a prominent sore on the lips. Three antiviral medications are currently available to speed the healing of cold sore. hey are most effective if used before the blisters form. They are available either as oral medications or in ointments and are very effective. They require a prescription, but the medications have a shelf-life of several years and are usually prescribed in enough quantity or with refills to handle several outbreaks. Beginning medication at the first sign of an outbreak may either prevent the appearance of blisters and the crust or reduce the size and duration of the cold sore. 

Self-Care

• Avoid getting infections such as colds and flu.

• Learn what might cause HSV-1 to become active and try to avoid those situations.

• Apply cold compresses or ice to relieve pain.

• Apply an over-the-counter (OTC) cold sore product, following the directions on the label.

• Take analgesics (such as aspirin) for pain. Use as directed.

• Wash hands frequently to avoid spreading the virus to other parts of the body or other people.

• Avoid touching the sores.

• When you're in the sun, apply zinc oxide or lip balm with sunscreen around the mouth and nostrils to block UV light, keep the skin soft and pliable and prevent cracking. This may reduce the likelihood of an outbreak.

Canker Sores

Canker sores usually occur inside the mouth, lips or cheeks. They can be red or yellowish-white with a red border. No one knows for sure what causes them. Unlike cold sores, canker sores are not contagious.

Treatment

There is no cure for canker sores. They usually go away on their own, but if you have unusually large, persistent canker sores or frequent outbreaks, your doctor may be able to prescribe a special mouthwash or other solution to ease your symptoms.

Self-Care

• Gargle or swallow one tablespoon of an antacid (such as Mylanta) four times a day, ideally after meals.

• Rinse your mouth with a solution of half hydrogen peroxide, half water.

• Avoid eating acidic foods such as citrus fruits or tomatoes. Salty, spicy or vinegary foods may irritate canker sores, as well. Milk, Jell-O, yogurt, ice cream, custard and other soft foods are often easier to tolerate.

• Avoid eating foods with sharp edges, such as potato chips.

• If they are painful, you can take an OTC pain reliever or swish a mixture of Milk of Magnesia and Benadryl Allergy liquid in the mouth and spit it out (do NOT swallow).

• To prevent foods from irritating them, you can apply medicine such as Anbesol, Oragel, Orabase and Zilactin-B directly to the sore.

• Call your health care provider if the canker sore lasts more than two weeks, you have a fever or feel sick when you have canker sores, or the sores are so painful that you cannot eat or drink.

Prevention

Good general health practices are the best precaution against mouth cold sores and canker sores:

• Eat a nutritious diet with lots of vitamin-rich fruits and vegetables.

• Get enough rest and exercise.

• Try to avoid getting colds and the flu.

• Wash your hands often with warm, soapy water.

• Avoid sharing glasses or utensils with someone who has any infection.

• Avoid smoking or chewing tobacco.

• Brush your teeth at least twice a day and floss daily.

• See your dentist regularly.

Decision Guide for Mouth Sores
Symptoms/Signs	Action
One or more red- or yellow-centered, craterlike sores inside the mouth, on the gums, or inside the lips and cheeks	Use self-care
One or more blisters on the outside of the mouth area	Use self-care
Mouth sores caused by poorly-fitting dentures or rough or broken teeth	Call provider's office
Recurring mouth sores	See provider
Possible exposure to a sexually transmitted disease	See provider
Facial swelling and signs of infection; severe pain and inability to eat	See provider
Watery or red eye or eye discomfort cause by bright light	See provider
Canker sore with loss of appetite or bad breath or that does not get better in 2 weeks or is very painful	See provider
Large, bleeding, painful ulcers on gums	See provider