It never fails. Every time you have a big meeting coming up or an important presentation to give, you develop an unsightly cold sore on your lip. You wake up with a small cluster of tiny, harmless-looking, white blisters, which quickly explode into a painful sore the size of Rhode Island. (OK, so maybe it just looks that big to you.)

Many people get confused about whether they have a cold sore or a canker sore. But that confusion is easily cleared up. Cold sores, also called fever blisters, are caused by the herpes simplex virus type 1, which is usually acquired in childhood through contact with infected saliva. The type 1 virus is believed to lie dormant in certain nerve cells of the body until it is activated by stress, anxiety, a cold, or excessive exposure to the sun and causes sores on your external lip or near your mouth or nose that last anywhere from 7 to 14 days. (Herpes simplex virus type 2, on the other hand, is transmitted through sexual contact and causes sores and ulcers in the genital area.)

Although many people use the terms "cold sore" and "canker sore" interchangeably, they are different. Unlike cold sores, canker sores are bacterial infections inside the mouth that are characterized by small, round, white areas surrounded by a sharp halo of red. And while cold sores are highly contagious, canker sores are not. (For more on canker sores, see Home Remedies for Canker Sores.)

You can't cure cold sores, and they like to keep coming back, usually to the scene of a previous visit. When a cold sore's not making itself a huge lip ache, it's snoozing in the nerves below your skin, just waiting for a reason to wake up. And what sets off its alarm clock?  
  • Fever  
  • Infection, colds, flu  
  • Ultraviolet radiation, such as a sunburn  
  • Stress  
  • Fatigue 
  • Changes in the immune system  
  • Trauma  
  • Food allergies  
  • Menstruation  
  • Dental work  
Fortunately, you don't have to suffer in silence with cold sores. In the next section, we'll look at simple home remedies to ease the discomfort of cold sores and and hasten the healing process.

For more information on conditions affecting the mouth, and helpful remedies for them, try the following links:
 This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Consumer Guide (R), Publications International, Ltd., the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.