Famciclovir
"I have a fluidy cold sore on my lip day 2, as I couldn't get any blistex, I've had to try the pills, praying they work as well as blistex, people are saying 4 days ? I bloody hope not , don't right you can kill a cold sore over night with blistex, remember to soak the cold sore and wipe the moist cold sore off , it will bleed , cover and repeat till dead"