I’ve had cold sores on and off for over thirty years. There are two remedies that have helped me. I take 2000 mg. of lysine as soon as I realize that I’m getting a cold sore and continue taking 1000 mg – 2000 mg three times a day until it is gone. Also, tea tree oil applied directly to the cold sore with a Q-tip 3times a day takes away the burning sensation and helps heal it faster. Anything I have ever put on a cold sore in the past would spread it. Between lysine and tea tree oil my cold sores don’t hurt, don’t spread, and heal much faster.