Yeah, they definetely help with outbreaks. I had a nasty inital cold sore outbreak, with like 10 sores at a time, laster two weeks, and the older ones actually got infected with a secondary bacterial infection. So definetely get some antivirals if this is your first sore.
You can expect that your subsequenty outbreaks will be much weaker and less frequent; even my second outbreak was only 1 sore, and it lasted a week and healed fully only in two, but now I have cold sores that don't even scab over, even if I use only 1 or 2 valtrex pills.
Call your provider and ask them to phone in a prescription for the cold sore doses of one of the herpes antivirals. Famvir and valtrex both have 1 day cold sore doses.
grace