I've suffered from cold sores my entire life. I hate when I feel that tingle coming on. I tried everything, and some things will help and shorten the duration, but I finally found what will stop if from even developing. My step-dad said he heard of people using their own urine. Just pass a q-tip through your own stream of urine, then dab it on the spot where a coldsore is developing. I was VERY reluctant to try this, but one day I felt one coming on and I was desperate. I tried it, and it worked!! Nothing came of it! I've tested this 2 or 3 times since, and can happily report its still working! I'm so happy to have found something that works.