Very potent, high affinity H3 agonist (KD = 50.3 nM) that displays > 200-fold selectivity over H4 receptors. Inhibits H3-mediated histamine synthesis and release in the CNS and stimulates H4-mediated eosinophil shape change (EC50 = 66 nM). Part of the Histamine H3 Receptor Tocriset™. (S)-(+)-α-Methylhistamine dihydrobromide (Cat. No. 0572) also available.