What causes cold sores?
Cold sores are a common viral infection. They are tiny, fluid-filled blisters on and around your lips and are often grouped together in patches. After the blisters break, a crust forms over the resulting sore and will usually heal in two to four weeks without leaving a scar.
Cold sores spread from person to person through close contact, such as kissing. They’re caused by a herpes simplex virus (HSV-1) closely related to the one that causes genital herpes (HSV-2). They are contagious even if you can’t see them yet.
Rinse your mouth with a solution of warm water mixed with 1/2 to 3/4 teaspoon of salt to help reduce inflammation.
Avoid hot, cold, or acidic foods and beverages temporarily.
Practice gentle brushing and flossing techniques.
Switch to a desensitizing toothpaste, such as Sensodyne or Colgate Sensitive.