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Causes for Recurring Cold Sores
Cold sores are something adults get pretty often, but what should you do if your child has one?
Pretty much every adult has had a cold sore at least once in their lifetime, and 20% of us have had recurring cold sores. They come back all the time because of fevers, stress, even sunburns, and being exhausted. All of those things take a toll on our immune systems, and the herpes simplex virus takes that opportunity to pop out a lovely cold sore.
Cold sores usually happen for the first time after your child has had contact with somebody with herpes. Now, don't worry. It's not that kind of herpes that causes cold sores. Once infected, the virus lives quietly in the body unless it's triggered by something, and then another crop of blisters shows up.
Cold sores only happen on one side of the mouth and appear in a cluster. So if your child has a different rash around their mouth, it's probably not a cold sore. Just before a cold sore shows up, your child might have a tingling or burning feeling on the outer lip, and it's usually in the same place that cold sores have been before.
The blisters normally burst, scab over, and dry up, causing the honey-crusted appearance we all know. After the sores dry up, they aren't as contagious anymore. The whole blister dry-up process takes up to two weeks. So if your child gets a cold sore, what can you do?
Home Treatment for Cold Sores
Well, ice helps a lot. Putting ice on the area that is tingling can actually stop the infection from progressing and being a full-fledged breakout. There are several cold sore ointments available over the counter to try, too. You can put them on your child as soon as the small bumps appear to help decrease the outbreak severity. Petroleum jelly can help as well.
Cold sores are contagious while they are in blister form. It's the fluid inside the blisters that has the virus. This is important to know so that you can take precautions during the most infectious time of the breakout. While cold sores are painful, annoying, and unsightly, they are quite common. Tylenol and Motrin can help the pain. If your child gets them repeatedly, ask your doctor if they're old enough for anti-herpes pills. There are a few kinds, but they aren't safe for all kids, and they do require a prescription.
If any sores show up by your child's eye, that's a true medical emergency, and they need to get on this medication as soon as possible.
updated: May 12, 2026
originally published: December 11, 2017
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