Pregnancy guide


Cold sores, sometimes called fever blisters, are groups of small blisters on the lip and around the mouth. The skin around the blisters is often red, swollen and sore. The blisters may break open, leak a clear fluid, and then scab over after a few days. They usually heal after several days to 2 weeks.

What causes cold sores?

Cold sores are caused by the herpes simplex virus. There are two types of herpes simplex virus: HSV-1 and HSV-2. Both virus types can cause lip and mouth sores and genital herpes.
The herpes simplex virus usually enters the body though a break in the skin around or inside the mouth. It is usually spread when a person touches a cold sore or touches infected fluid, kissing an infected person, or touching that person’s saliva.

What are the symptoms?

The first symptoms of cold sores may include pain around your mouth.
After the blisters appear, the cold sores usually break open, leak a clear fluid, and then crust over and disappear after several days.
For some people, cold sores can be very painful.

How are cold sores treated?

Cold sores will usually start to heal on their own within a few days. But if they cause pain or make you feel embarrassed, they can be treated.
Treatment may include skin creams, ointments, or sometimes pills.

How can you prevent cold sores?
  • Avoid coming into contact with infected body fluids, such as kissing an infected person.
  • Avoid sharing eating utensils or drinking cups.
  • Avoid the things that trigger your cold sores, such as stress and colds or the flu.
  • Always use lip balm and sunscreen on your face.
  • Avoid sharing towels or toothbrushes.
  • Make sure to wash your hands often, and try not to touch your sore.
Treatment of recurrent cold sores.
  • Topical creams and ointments can reduce pain, itching and healing time.
  • Oral antiviral medications may be used when the first symptoms develop.
  • Oral antiviral medications may also be taken daily to prevent recurring cold sores, in people who have frequent and painful outbreaks.

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Guide summary