Carbamazepine. Neuronal Nav Channel Inhibitor.
Voltage-gated sodium channels (VGSC, Nav) play a critical role in excitability of nociceptors (pain-sensing neurons). The peripheral-specific sodium channels Nav1.7, Nav1.8 and Nav1.9 are particularly important in the pathophysiology of different pain syndromes and hence, thought to be potential targets for pain therapeutics.
Carbamazepine is a potent and state dependent inhibitor of neuronal Nav channels. It is one of the most commonly prescribed antiepileptic drugs and has long been established as a treatment for neuropathic pain. High doses of carbamazepine are effective in ameliorating symptoms of patients with paroxysmal extreme pain disorder (PEPD) because this disorder involves changes in Nav inactivation, a process that is modulated by Nav blockers. In a recent investigation patients with inherited erythromelalgia, characterized by a mutation in Nav1.7 (SCN9A) and a modified fast inactivation of Na+ current is present, reported an improvement of symptoms when treated with Carbamazepine.
In addition, clinical data also suggest that Carbamazepine can reduce aura and migraine attacks.
Ion Channel Modulators; Voltage-Gated Na+ Channel Blockers.