[The classification and mechanism of the hypnotics].

The various hypnotics are currently available. Today benzodiazepine (BZ) derivatives are most used, but non-benzodiazepines (non-BZ), are being used. BZs and non-BZs are classified four groups by means of pharmacokinetics, (1) ultra-rapidly elimination hypnotics, (2) rapidly elimination hypnotics, (3) relatively slow elimination hypnotics and (4) slow elimination hypnotics. BZs modulate gamma-aminobutyric acid (GABA)-ergic transmission, and specific receptors exist in the brain. GABA is the most abundant inhibitory neuro-transmitter in the central nervous system. BZs alter sleep by binding receptor-GABA receptor-chloride channel.