lorazepam, drug used in the treatment of anxiety disorders, sleep disorders, and epilepsy, as a sedative, and to induce amnesia, generally in the context of surgical procedures. Lorazepam was approved for these uses by the U.S. Food and Drug Administration (FDA) in 1977. It is marketed under various brand names, including Ativan, Temesta, Lorazepam Intensol, and Loreev XR. It may be taken orally or may be injected. When given by intravenous injection, it takes effect quickly, usually within 1 to 3 minutes.
Lorazepam is a type of benzodiazepine. It exerts its effects by binding to gamma-aminobutyric acid A (GABAA) receptors in the central nervous system. In doing so, the drug increases the receptors’ affinity for GABA, an inhibitory neurotransmitter. Enhanced GABA activity reduces the transmission of neural impulses in the brain—particularly in the amygdala, a region associated with anxiety, and the cerebral cortex, where excessive activity is associated with seizures.
Lorazepam also has various non-FDA-approved uses, such as in the alleviation of symptoms of alcohol withdrawal, in calming extremely agitated patients, and in treating psychogenic catatonia and delirium panic disorder. It may also be used to prevent anticipatory nausea and vomiting associated with chemotherapy.
The most common side effects associated with lorazepam include sedation, dizziness, weakness, and unsteadiness. Reduced coordination, confusion, changes in appetite, reduced sexual function, and changes in menstruation and bowel and bladder function may also occur. More-serious adverse effects include dependency, tachycardia (increased heart rate), and low blood pressure. Use of lorazepam during pregnancy has been associated with withdrawal symptoms in the newborn.