HRH3 and Anxiety: The reported results for numerous H3R antagonists/inverse agonists on anxiety models also differed momentously, with the most observed effect being the lack of any effects on anxiety-like behaviors assessed for ABT-239, ciproxifan, clobenpropit, DL77, and E159 in both rats and mice (Femenía et al., 2015; Alachkar et al., 2017; Masini et al., 2017; Eissa et al., 2018; Alachkar et al., 2019; Chauveau et al., 2019; Eissa et al., 2019; Soliani et al., 2020; Trofimiuk et al., 2020).