Cold sores usually go way within 2 weeks, although they can go away in just 2 to 3 days. Cold sores are also known as fever blisters. They are small blisters that generally cluster around the mouth.
Cold sores are actually a type of herpes known as the herpes simplex virus. The virus itself never goes away, which is why people continue to have outbreaks of cold sores throughout their lives. However, avoiding stress, cold or flu, and using protection for the sun can help prevent outbreaks. Also, avoiding fluid contact with people who have active outbreaks can also help with preventing new cold sores from popping up.