Valerian is a staple medicinal herb used throughout Europe. And, unlike benzodiazepines, using valerian to treat insomnia increases the amount of time spent in deep and rapid eye movement (REM) sleep. Valerian contains chemicals with strong muscle-relaxant and sedative properties called valepotriates. All parts of the plant contain these chemicals, but they are most concentrated in the roots. Ironically, even valerian preparations without valepotriates have helped some people to fall asleep, raising the possibility that some still unidentified chemical, or a reaction amongst various compounds in the root, may produce a calming effect.