BENZODIAZEPINES are a class of drugs primarily used for treating anxiety, but they also are effective in treating several other conditions. The exact mechanism of action of benzodiazepines is not known. All benzodiazepines affect gamma-amino butyric acid (GABA), a neurotransmitter chemical that nerves use to communicate with one another. Since scientists believe that excessive activity of nerves in the brain may be the cause of anxiety and other psychological disorders, and GABA reduces the activity of nerves in the brain, benzodiazepines may be working by increasing the effects of GABA in the brain and spinal cord.