licorice is obtained from glycyrrhiza glabra (g. glabra) in iran. glycyrrhizin is the main constituent of g. glabra and has several pharmacological effects. it is hydrolyzed to glycyrrhetic acid (ga) in the intestine after oral administration. in this study, a novel hplc method was used to determine the concentration of ga in rat plasma after oral administration of licorice aqueous extract. the...