Thioperamide (maleate) is a selective histamine H3 receptor antagonist that crosses the blood-brain barrier. This compound binds to rat cerebral cortical cells in vitro with a pKi value of 8.4 and inhibits histamine binding in vivo with an ED50 value of 1 mg/kg.[1] At a dose of 5 mg/kg thioperamide (maleate) inhibits kindled seizures in rats by decreasing histamine and gamma-aminobutyric acid.[2]

Reference:
[1]. Meir, G., Apelt, J., Reichert, U., et al. Influence of imidazole replacement in different structural classes of histamine H3-receptor antagonists. European Journal of Pharmaceutical Sciences 13, 249-259 (2001).
[2]. Harada, C., Fujii, Y., Hirai, T., et al. Inhibitory effect of iodophenprofit, a selective histamine H3 antagonist, on amygdaloid kindled seizures. Brain Research Bulletin 63, 143-146 (2004).