The plant’s dried root contains valepotriates, which may have calming effects. (See also Overview of Dietary Supplements.)
People take valerian mostly as a sedative and sleep aid, especially in parts of Europe. Studies have suggested that valerian improves sleep quality and shortens the time needed to fall asleep. In menopausal women with difficulty sleeping, valerian may improve sleep quality.
Some people take valerian for headaches, depression, irregular heartbeat, and trembling, although evidence is insufficient. It is usually used for short periods of time (2 to 6 weeks). There is not enough scientific evidence to determine whether valerian is effective for these conditions. There is now interest in studying valerian to treat obsessive-compulsive disorder.
The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.
National Institutes of Health (NIH), National Center for Complementary and Integrative Health: General information on the use of valerian as a dietary supplement