What ion channel do local anesthetics primarily block?

Local anesthetics (lidocaine, articaine, bupivacaine) block voltage-gated sodium (Na+) channels. They bind the channel in the INACTIVATED state (use-dependent block), preventing Na+ influx and thus action potential generation/propagation. No Na+ influx = no depolarization = no pain signal. K+ channels, Ca channels, and Cl channels are not the targets.