What Causes Cold Sores in Your Mouth?

Cold  sores  are a very common infection and it has been estimated that 80% percent of the United States population has been exposed to herpes simplex virus, the virus which causes cold  sores .

An interesting fact to note – even if a person has been infected with the herpes virus, they may not always experience of an epidemic or have an outbreak. This is because the immune systems of certain people have the ability to completely suppress the virus.


Cold  sores  are caused by the herpes simplex virus type 1 (HSV-1). The HSV-1 virus is transmitted from person to person through saliva and even with indirect contact like drinking from the same glass or using the same toothbrush. It is most frequently appear as small blisters on the lips and can be very painful for those who experience them.

It is usually occur inside the mouth and are most frequently found on the gums or hard palette, the roof of the mouth. If the injury appears inside the mouth, especially in soft tissues, is more likely to be a thrush, not a cold  sore . It may also appear on the fingers, which is called Herpes Whit low.


There are several factors that may influence or “trigger” an outbreak, however, this an outbreak of  sores  does not seem to be related to a time when the immune system is depressed or tired.

Outbreaks of cold  sores  can sometimes be caused by the following:

1. Being overly tired and run down, physical exhaustion

2. A females menstrual cycle

3. Pregnancy

4. Drinking a lot of alcohol

5. Over exposure to strong sunlight

6. Conditions that compromise a person’s immune system

7. A person whose immune system does not operate normally

8. Long-term stress

9. Fatigue

10. Ultraviolet light – tanning beds

11. Irritation of the skin -sunburn

12. Diet and certain foods – it is important to note what trigger foods are causing you to have outbreaks of  sores  and then is recommended that you go talk to your doctor about the condition as you may have a food allergy which is causing you to experience more than  sores .

13. Illness – especially those that are associated with a fever

14. Extreme temperatures – both hot and cold weather

15. Steroids – such as asthma medicine

16. And anything that lowers your immune system or causes local injury can trigger recurrences.


1. Avoid kissing and skin contact with people while blisters are visibly present. The virus can spread easily as long as there are moist secretions from the blisters.

2. Avoid sharing items such as utensils, towels, chap-stick and other items which can spread the virus when blisters are present.

3. Keep your hands clean. Wash hands thoroughly before and after touching another person you know has cold  sores .

4. Be careful not to touch other parts of your body – your eyes and genitals can be particularly susceptible to the virus.

5. Avoid triggers. If possible, try to avoid or prevent conditions that stress the body, such as getting a cold or the flu, not getting enough sleep, or stay in the sun for long periods of time to apply sunscreen.

6. Use a sunscreen. Apply sunscreen to the lips and face before prolonged exposure to the sun – winter and summer – to help prevent cold  sores .