WHY WOULD A COLD SORE GO AWAY THEN COME BACK, GO AWAY COME BACK ETC ETC ETC????
That is what they do.Â The virus that causes them lives safely inside a nerve ganglion in your head and comes out periodically, causing a cold soreÂ when you get a cold or when other triggering events (fever, trauma, sunlight, allergy)Â occur.
For more information:
Go to the Dental and Oral Health (Adults) health topic.