A benzodiazepine with anxiolytic, anti-anxiety, anticonvulsant, anti-emetic and sedative properties. Lorazepam enhances the effect of the inhibitory neurotransmitter gamma-aminobutyric acid on the GABA receptors by binding to a site that is distinct from the GABA binding site in the central nervous system. This leads to an increase in chloride channel opening events, a facilitation of chloride ion conductance, membrane hyperpolarization, and eventually inhibition of the transmission of nerve signals, thereby decreasing nervous excitation.