(Fever Blisters; Herpes Labialis; Herpes Stomatitis; Herpes Simplex)
Cold sores – Definition
Cold sores are small, painful, fluid-filled blisters. They are usually found at the border of the lip.
Cold sores – Causes
Cold sores are usually caused by the herpes simplex 1 virus. Rarely, it is caused by the herpes 2 virus. Herpes 2 virus causes genital herpes. The two viruses are related, but different.
In most cases, people contract the virus as young children. The first episode of illness with herpes simplex 1 virus can cause a body wide illness. Then the virus lies quiet in the skin until it is reactivated. This is when the virus causes cold sores.
You may get the virus from:
- Contact with the fluid from a cold sore of another person, or sores of genital herpes
- Contact with the eating utensils, razors, towels, or other personal items of a person with active cold sores
- Sharing food or drink with a person with active cold sores
- Contact with the saliva of a person who has the herpes simplex virus
Cold sores – Risk Factors
An infection with the herpes virus is very common. Everyone is considered at risk for a herpes infection.
If you have a herpes infection, factors that can trigger cold sores include:
- Infection, fever, cold, or other illness
- Exposure to sun
- Physical or emotional stress
- Certain drugs
- Weakened immune system
- Physical injury or trauma
- Dental or other oral surgery
Cold sores often form without a known trigger.
Cold sores – Symptoms
The initial herpes simplex 1 infection can cause flu-like symptoms. The recurring infections will lead to cold sores.
A cold sore occurs most often on the lips but can occur in the mouth or other areas of the skin. You may have some symptoms the day just before a cold sore appears. You may notice some itching, tingling, burning, or pain in the area the cold sore appears. Cold sore blisters:
- Are small, painful, fluid-filled, red-rimmed blisters
- Will dry up with a crust and a shallow sore after a few days
Cold sores – Diagnosis
The doctor will ask about your symptoms and medical history. The blisters will be examined. Usually, the doctor can easily diagnose a cold sore by looking at it. In rare cases, the doctor may need to take a piece of a blister. The piece will then be analyzed. A blood sample may also be taken for testing.
Cold sores – Treatment
Cold sores will usually heal within two weeks even without treatment. However, certain treatments may help decrease symptoms. They may also shorten the time that you have a sore. Treatment options include:
- To reduce pain consider:
- Nonprescription cold sore/fever blister cremes and ointments
- Putting ice on blisters to lessen pain
- Mouthwash with lidocaine — to treat cold sores in the mouth
- Medications that may shorten the outbreak include:
- Antiviral cream or ointments — may also help decrease pain
- Oral antiviral medications — may be given the moment you feel a cold sore coming on or could be taken on a regular basis to suppress frequent outbreaks. Examples include:
- Acyclovir (Zovirax)
- Valacyclovir (Valtrex)
- Famciclovir ( Famvir)
- Avoid rubbing or scratching blisters. This can delay healing. It can also increase your chance of a second infection.
Cold sores – Prevention
To prevent the oral spread of the herpes simplex 1 or 2 virus:
- Be careful around people who have active cold sores. Avoid skin contact and kissing. Do not share food, drink, or personal items.
- Avoid performing oral sex on a person with active genital herpes.
- If you have an active cold sore, avoid touching the infected area. This will help keep you from spreading the virus to other people and/or other parts of your body. If you do touch the area, wash your hands.
The herpes virus never leave your body once you have it. There is no cure for the infection. If you already have a herpes infection, to prevent future outbreaks of cold sores or blisters:
- Avoid long periods of time in the sun.
- Use sun block on lips and face when in the sun.
- Get adequate rest and relaxation. Try to minimize stress.
- If you have outbreaks often, talk to your doctor about taking antiviral medicines.