To speed up the healing time of cold sores, I use a combination of the following: Retin-A cream or Alpha Hydroxy cream, hydrogen peroxide, witch hazel, Bag Balm, and Blistex (all are available in drug stores).
I clean the sore with hydrogen peroxide, the dry. Then I dab on some witch hazel. When dry, rub in large amounts of Retin-A or Alpha-Hydroxy cream (this will dry it out). Finish by covering with Bag Balm (or, Vaseline) to keep it from cracking. This will help heal the sore, and also keep it from itching and burining.
When the sore has scabbed over, Blistex (in the tube) is great to keep it from cracking and will also lift up some of the scab.