m3-Huwentoxin IV (m3-HwTx-IV) is a potent inhibitor of sodium channels (NaV), exhibiting half-maximal inhibitory concentrations (IC50s) of 3.3 nM for hNaV1.7, 6.8 nM for hNaV1.6, 7.2 nM for hNaV1.3, 8.4 nM for hNaV1.1, 11.9 nM for hNaV1.2, and 369 nM for hNaV1.4 in the QPatch assay. It also dose-dependently alleviates spontaneous pain in a rodent model when induced by the NaV1.7 activator OD1 [1].