Since the introduction of Librium in 19601 and the subsequent discovery in 19772* 3 of its mode of action via the 7-aminobutyric acid (GABA)/benzodiazepine receptor (BzR) system, the benzodiazepines have enjoyed widespread use rivaled by few other classes of compounds. Benzodiazepine agonists effect a variety of pharmacological actions, but are far less toxic than, for example, barbiturates. Benzodiazepine receptor ligands produce their ...