Salt acts as an anti-inflammatory and therefore it arrests cold sores very effectively, sometimes in only a matter of a few hours. What it does is draw out the fluids in the cold sore, causing it to become smaller and heal faster.
You need to put a small quantity of salt directly onto the cold sore using a cotton swab or your (clean) finger, and leave it on for about 10 minutes, holding it there with your finger if necessary. If the cold sore isn’t moist enough for the salt to stick, add a little water. Repeat this two or three times a day.
You’re certain to experience some burning and discomfort, particularly if the cold sore is raw. This is perfectly alright and you shouldn’t be concerned, unless it becomes extreme. In that case, rinse the salt off immediately.
Some people find that mixing the salt with toothpaste (not the gel kind) or applying it with a wedge of lime gives greater relief than salt alone.
Always be certain that your hands are clean when applying salt to your cold sore to prevent the transfer of bacteria. Also, if you hold an ice cube to your cold sore before using the salt it will help to numb the area and reduce the stinging.