Bupivacaine inhibits NMDA receptor-mediated synaptic transmission in the dorsal horn of the spinal cord, an area critically involved in central sensitization[1]. Bupivacaine influences the voltage dependency of channel activation and steady-state inactivation by shifting the membrane potential of half-maximal activation/inactivation toward somewhat more negative membrane potentials. In their inactivated state, SCN5A channels are slightly sensitive toward Bupivacaine IC50=2.18±0.16 μM[2]. Bupivacaine reversibly inhibits the SK2 channel in a dose-dependent manner with the IC 50 of 16.5 µM[3].