Mambalgin 1 TFA, a selective inhibitor of ASIC1a (with IC50 values of 192 nM for human ASIC1a and 72 nM for the ASIC1a/1b dimer), preferentially binds to the channel in its closed/inactive state. It demonstrates selectivity for ASIC1a over a range of other channels, including ASIC2a, ASIC3, TRPV1, P2X2, 5-HT3, Nav1.8, Cav3.2, and Kv1.2. In vivo, Mambalgin 1 TFA effectively prolongs the latency of the withdrawal response in mouse tail-flick and paw-flick tests.