I am having a little difficulty understanding this concept, and was hoping someone might be able to help me. If this is not the cost appropriate section for this question, I apologise in advance! What I was wondering is, what happens to a local anaesthetic molecule after it dissociates from the sodium channel? Does it enter circulation and undergo biotransformation, or can it be transported to another site and exert further action? Also, what causes this dissociation in the first place? Many thanks.