Lorazepam is a drug used for treating anxiety. It is in the benzodiazepine family, the same family that includes diazepam (Valium), alprazolam (Xanax), clonazepam (Klonopin), flurazepam (Dalmane), and others. It is thought that excessive activity of nerves in the brain may cause anxiety and other psychological disorders. Gamma-aminobutyric acid (GABA) is a neurotransmitter, a chemical that nerves in the brain use to send messages to one another. GABA reduces the activity of nerves in the brain. Lorazepam and other benzodiazepines may act by enhancing the effects of GABA in the brain. Because lorazepam is removed from the blood more rapidly than many other benzodiazepines, there is less chance that lorazepam concentrations in blood will reach high levels and become toxic. Lorazepam also has fewer interactions with other medications than most of the other benzodiazepines. The FDA approved lorazepam in March 1999.