Sodium channel protein type 9 subunit alpha, Sodium channel protein type 10 subunit alpha, and Sodium channel protein type 11 subunit alpha (Nav1.7/1.8/1.9)

Voltage-gated sodium channels Nav1.7, Nav1.8, and Nav1.9 (encoded by the genes SCN9A, SCN10A, and SCN11A) are a specialized subset of sodium channels primarily expressed in peripheral sensory neurons, particularly nociceptors (Lai et al., 2023). These channels play distinct but complementary roles in pain signaling: Nav1.7 acts as a threshold-setting channel that initiates action potentials, Nav1.8 carries the majority of the current during the action potential upstroke, and Nav1.9 modulates resting membrane potential and repetitive firing (Advanced Spine and Pain, 2026; NIH, 2025). Because of their restricted peripheral expression, they are high-priority targets for non-opioid analgesics designed to avoid central nervous system side effects like addiction and respiratory depression (Erythromelalgia.org, 2018). Mutations in these channels are directly linked to human pain disorders, including erythromelalgia, paroxysmal extreme pain disorder, and congenital insensitivity to pain (Frontiers in Pharmacology, 2025). Recent drug development has produced subtype-selective inhibitors such as the FDA-approved Nav1.8 inhibitor suzetrigine (VX-548), as well as multi-target molecules like VX-150 and ANP-230 that block the entire peripheral pain-signaling network (Vertex Pharmaceuticals, 2025; JCI, 2025). However, achieving high selectivity remains a significant challenge, as off-target inhibition of other sodium channels can lead to safety concerns such as cardiovascular toxicity or anosmia (DrPress, 2023).

Other names

Peripheral voltage-gated sodium channelsNociceptive sodium channelsSCN9A/SCN10A/SCN11ATTX-sensitive and TTX-resistant peripheral sodium channels

Selective blockade of sodium ion influx, stabilization of the closed or inactivated state of the channel, and inhibition of action potential propagation in peripheral nociceptors.