What Causes Cold Sores To Flare Up?

Cold sores can be painful and are caused by the herpes simplex virus. The sores can cause the skin around the blister to get red, puffy, and irritated. It is thought that 90 percent of adults will have one within their lives with the first one being the worst. Some people develop antibodies to fight the infection and will never get them again. However, 40 percent of people will have recurrent cold sores.

Unfortunately, there is no cure for cold sores, but there are some treatments that you can use to ease the symptoms or make them go away faster.

Causes of Cold Sore Flare-Ups

Cold sores are caused by the herpes virus that enters through the skin or the mouth. If you touch a cold sore or touch the person’s infected fluid (even through shared cups, razors, a kiss, or touching the infected person’s saliva), you can get them too. They commonly show up around the mouth, but can be spread to other parts of the body as well. The sores can show up as many as twenty days after the initial infection.

Some people get symptoms when they are stressed, get a cold, or have the flu. Avoiding these situations can help. Also, try to avoid being in too much sunlight, or at least use sunscreen and chapstick to protect your skin and lips from the sun. Allergies or certain foods also can trigger an outbreak. Even menstruation has been thought to trigger the sores for some people. Talk about adding insult to injury there!


Symptoms depend on different people. Some people have the virus, but show no signs of it. Others get pain around their mouth, fevers, swollen glands in the neck, or a sore throat. The cold sores appear, then the blisters break open and ooze out a clear liquid. After a few days to up to a couple weeks, the sores crust over and go away.


There is no cure for the disease, but you can use some treatments to make the cold sores go away a little faster or ease the pain you may get from them. Your doctor may recommend skin cream, ointments, or even pills as treatment options.

When you do have a sore, make sure to wash your hands more frequently and avoid touching the sore. You can still spread it to other areas of your body and to others so it is best to limit contact with the sore. If the infection spreads to your eye, you can become blind. If it spreads to your brain, you could develop meningitis or encephalitis.

Avoid Getting Cold Sores in the First Place

The best way to avoid getting cold sores is by not sharing utensils or items that might come in contact with someone’s saliva, mouth, lips, or skin. That means, do not share lipstick, facial makeup, lip gloss, straws, toothbrushes, towels, or food with others. You may think it is too rude to refuse to share food or items with others, but you can still take precautions and share things with others. Prevention is key here. Otherwise, you may have herpes simplex virus to deal with for the rest of your life.