The voltage gated sodium channel isoform Nav1.2 is involved with axon potential initiation and conduction. Nav1.2 is the target of antiepileptic drugs and the probable target causing side effects of centrally active local anaesthetics. It is detected in relative abundance on myelin-deficient areas on axons in the central and peripheral nervous systems. Demyelinated axons expressing Nav1.2 are much less susceptible to axonal degeneration. The action of a drug on Nav1.2 sodium channels may interfere with the fine balance between axon growth and nerve impulse transmission.