A friend and her husband were staying over the weekend and on Friday afternoon she said there was a cold sore coming up. I told her to spray with silver water (above the lip) and she did it each 2-3 hrs the first evening. Next morning she thought it might be going away because it would normally be very sore and angry by this stage. She applied it about 5 times that Saturday, then on the Sunday and it was almost completely gone. She had had these regularly for decades and was amazed because that is the first time it was ever stopped.
She has used it many times since with the same results.