List of products in the National Drug Code with proprietary name . This medication is used to treat serious seizures that do not stop (status epilepticus). It is also used before surgeries or procedures to cause drowsiness, decrease anxiety, and cause forgetfulness about the procedure or surgery. Lorazepam belongs to a class of medications called benzodiazepines, which produce a calming effect on the brain and nerves (central nervous system). It is thought to work by increasing the effect of a certain natural chemical (GABA) in the brain.