Sodium bromide (NSC 77384; Sanibrom 40) is a GABA-ergic system modulator that crosses the blood-brain barrier, and it effectively reduces and blocks epileptiform discharges. Sodium bromide exerts significant anticonvulsant effects by enhancing GABA-ergic inhibitory functions, such as increasing the amplitude of inhibitory postsynaptic currents and paired-pulse inhibition. Sodium bromide specifically enhances stimulation-induced extracellular alkalosis without affecting baseline pH or subsequent acidosis processes. Sodium bromide exhibits species-specific pharmacokinetic characteristics, competes with chloride ions for renal tubular reabsorption sites, and serves as a marker for extracellular fluid volume. Sodium bromide can be used in the research of epilepsy and related neurological diseases.