Lorazepam is a prescription anti-anxiety drug used to treat anxiety disorders and anxiety associated with depression; insomnia, panic attacks, and seizures. Common side effects are weakness, dizziness, unsteadiness, and headache. Lorazepam belongs to a class of medications called benzodiazepines. It is thought that benzodiazepines work by enhancing the activity of certain neurotransmitters in the brain. Lorazepam is used in adults and children at least 12 years old to treat anxiety disorders. Ativan (lorazepam) belongs to a class of medications called benzodiazepines. It is thought that benzodiazepines work by enhancing the activity of certain neurotransmitters in the brain. Ativan is used in adults and children at least 12 years old to treat anxiety disorders. Lorazepam is a benzodiazepine that works in the brain to relieve symptoms of anxiety. Benzodiazepines are central nervous system (CNS) depressants, which are medicines that slow down the nervous system. This medicine is available only with your doctor's prescription. Find patient medical information for Lorazepam (Ativan, Loreev XR) on WebMD including its uses, side effects and safety, interactions, pictures, warnings, and user ratings Why is this medication prescribed? Lorazepam is used to relieve anxiety and treat insomnia. Lorazepam is in a class of medications called benzodiazepines. It works by slowing activity in the brain to allow for relaxation. Lorazepam, sold under the brand name Ativan among others, is a medication of the benzodiazepine and depressant category. [15]. It inhibits activity of the central nervous system, and has anxiolytic and hypnotic effects.