Ativan is the brand name for Lorazepam, which is a benzodiazepine. Pharmacologically, It is used a mild tranquilizer, sedative, and central nervous system (CNS) depressant to treat anxiety and tension and insomnia. It can be taken orally in the form of tablets or can be injected when in liquid form. The effects of Ativan are usually felt one to five minutes after receiving it intravenously, 15 to 30 minutes after muscular injection, or 1 to 6 hours after oral administration.