SN instructed patient about the Restoril ( temazepam ) is a benzodiazepine. Temazepam affects chemicals in the brain that may be unbalanced in people with sleep problems ( insomnia ). Restoril is used to treat insomnia symptoms, such as trouble falling asleep or staying asleep. Restoril works by slowing down the central nervous system ( brain ), causing drowsiness which helps patients fall asleep.