Penciclovir
"This medicine is AMAZING. I woke up with the tingling feeling Wednesday morning by the afternoon it started taking its course. I picked up Denavir from the pharmacy that afternoon and started applying every two hours like it recommends. It has kept the cold sore at an absolute minimum. It hasn't even developed fully and I think it's already on its way out. 3 days! AMAZING! Its super expensive if you don't have insurance but if you do get this."