What Triggers a Cold Sore Outbreak?

If you are one of the millions of Americans that suffer from cold sores, you are probably wondering what triggers them. There are many things that can trigger a cold sore outbreak, and some will surprise you.

Weakened Immune System

If your immune system is weak due to other factors, such as a cold or other virus, then cold sores may form. They may also form because of the cold itself or if you are running a fever. As soon as you start to feel sick, it is important to make sure you get plenty of rest, fluids and vitamin C. This will help decrease the cold sore outbreak time.


Too much exposure to the cold or the hot weather may bring on an outbreak of cold sores. If you spend too much time in the hot sun, it can dry out your skin and cause an outbreak. This is due to the UV rays. If you spend too much time in the cold weather, the wind and bitter cold can also cause outbreaks.

Being Tired or Stressed

When your body is tired all the time, it can cause an outbreak. It is important to allow your body to recover from being overly tired. If you are a person that overwhelms yourself with work and kids, or whatever your life consists of, your body may be trying to tell you it is time to slow down. Managing your time wisely may help to decrease the number of cold sore outbreaks you may have.

Being stressed may also cause an outbreak. Being stressed out causes the immune system to break down. This may cause the outbreak of cold sores. Dealing with your stress is important if you are a person who frequently has outbreaks.


Hormones can play a big role in cold sore outbreaks. Women's hormones can cause outbreaks during menstruation. Cold sores may also develop if a woman's hormones are imbalanced. This can be due to pregnancy, menopause or other changes.

Injury to the Mouth

Cold sore may develop if you have had an injury to the mouth. Many times, if you have been to the dentist, your mouth has been opened for a long time with the dentist working in it. This can cause dryness and soreness to the lips, which can cause an outbreak. Since there is not much you can do about this at the dentist's office, try to hydrate your lips before and after you go to the dentist. This may help a little with the dryness of your lips. Also, talk to your dentist if this is a persistent problem, and he can help give your mouth breaks during treatments.

There are many causes of cold sore outbreaks. Trying to determine what causes outbreaks may help you to reduce the number of outbreaks you will have. This may be your best prevention against cold sores.

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