XE 991 dihydrochloride, a Kv7 (KCNQ) channels blocker, potently inhibits Kv7.1 (KCNQ1), Kv7.2 (KCNQ2), Kv7.2 + Kv7.3 (KCNQ3) channel, and M-current with IC50s of 0.75 μM, 0.71 μM, 0.6 μM, and 0.98 μM, respectively.IC50 & Target: IC50: 0.75 μM ( Kv7.1 channel), 0.71 μM (Kv7.2 channel), 0.6 μM (Kv7.2 + Kv7.3 channel), 0.98 μM (M-current)In Vitro: XE 991 dihydrochloride possesses an EC50 of 490 nM for enhancement of [3H]ACh release from rat brain slices, and shows good in vivo potency and duration of action[2].