LML134 (LML-134) is a potent and selective inverse agonist of the human Histamine H3 Receptor (H3R), demonstrating high affinity with Kis of 0.3 nM in cAMP assays and 12 nM in binding assays. This small molecule is a valuable research tool for investigating H3R function in neurological disorders, supporting both in vitro mechanistic studies and in vivo preclinical research.