Voltage-gated sodium (Na(v)) channels are highly sensitive to membrane potential and have fast gating kinetics. Patch clamp electrophysiology has long been the gold standard for studying these channels. Combining high throughput with high information content/accuracy, automated patch clamp technologies have emerged as critical tools in ion channel drug discovery. Described in this unit is the use of QPatch, one of the automated patch clamp systems, to study Na(v) channel function and pharmacology.