Cold sores are caused due the infection by herpes simplex virus. Have patience as it would take at least a week to heal a cold sore. Follow the remedies regularly for the sore to heal faster.

• Do not bother the cold sore if it doesn’t bother you and keep it dry as far as possible. Apply sunscreen lotion when you step out in sun, as cold sores are very sensitive to sunlight.
• With the onset of a cold sore apply ice on it. This will prevent further development of it.
  
• Take raw cold milk in a cotton ball and compress it over the cold sore. This will help to speed the healing process.
  
• Replace your toothbrush as soon as you get the infection to avoid its spread. Do not place tooth brush in the bathroom and once the sore is gone replace it again.
  
• Apply aloe vera juice over the cold sore. This will help to speed up the healing of a cold sore.  
  
• Reduce the consumption of too salty foods, oatmeal, peanuts, peas, colas, beer, cashew nuts and chocolates in the diet.
  
• Relax, avoid any kind of stress. Be physically active and exercise to boost your immune system.
  

To read more on cold sores you can refer the following link –
www.home-remedies-for-you.com/remedy/Cold-Sores.html - 72k