For non prescription you can try "lipactin" all it does is dry it out, takes about a week to heal.
For prescription you can get "zovirax". I've tried the cream, it works a little faster than lipactin, but you have to "liberally" apply this white cream to it, so you look like a goof. Theres also a pill form of zovirax i haven't tried.
I got prescribed this stuff called "valtrex" its a pill, pop 4 when you feel it coming and then pop 4 12 hours later. Supposed to cut it down to a few days i believe. Its actually for genital herpes, but i guess you can use it for herpes simplex. I have yet to try it, i keep it on hand just in case though.
Cold sores suck ass