Article Translations: (Spanish)
A cold sore is a small blister that forms on the outer edge of the lip. Some people call cold sores fever blisters.
Cold sores can appear one at a time or in little bunches. They're filled with fluid, then crust over and form a scab before they go away. They last about a week or two and usually don't need any treatment.
Cold sores are caused by a virus. The name of the virus is herpes (say: HUR-peez) simplex virus type 1 (or HSV-1, for short). Someone can get the virus by kissing someone with a cold sore or sharing personal items (like a towel, drinking glass, fork, or spoon) with them.
After a kid gets a cold sore, the HSV-1 virus stays in their body even after the cold sore goes away. And sometimes, the virus can make cold sores come back again.
If you know someone who has a cold sore, try not to catch their germs. Don't kiss them or use their drinking glass, fork, spoon, or towels.
Cold sores usually go away on their own, but sometimes doctors will treat them with medicine.
While you're waiting for the cold sore to go away:
Taking good care of yourself may help prevent cold sores from coming back. But sometimes they come back without a clear reason.
Here are some tips that may help prevent another cold sore:
Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.
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