Valerian for Insomnia

Valerian is a medicinal herb that may be useful in the treatment of insomnia. It is thought to increase the level of GABA in the synaptic cleft.
The National Sleep Foundation reports:
Herbal remedies are used around the world for a variety of ailments, including sleep disorders. For many years, sleep researchers have studied herbal compounds such as valerian in hopes of finding new treatments for insomnia and other sleep problems. Sold in the United States as a dietary supplement and loosely regulated by the FDA as a food substance, valerian is available in the form of a tea, tincture, capsule, or tablet. People try valerian as a natural sedative for nervousness and insomnia. With so many Americans suffering from insomnia - 54% report symptoms at least a few nights a week or more, according to the National Sleep Foundation’s 2005 Sleep in America poll – it’s no wonder that insomnia sufferers would seek out remedies.
But does valerian really work? The latest word comes from the Office of Dietary Supplements (ODS) at the National Institutes of Health (NIH) in their recently updated and thorough fact sheet on valerian for the treatment of insomnia. It states that while evidence from some clinical studies suggests that valerian may be useful for insomnia, others do not. Also, in its State-of-the-Science Conference Statement on Manifestations and Management of Chronic Insomnia in Adults, NIH found that only non-benzodiazepine medications and cognitive behavioral therapy (CBT) have evidence for safety and efficacy to support their use for the treatment of insomnia. This report also found that insomnia often occurs in association with other disorders, in which case, seeking medical treatment would be recommended over the use of self-treatments such as valerian.
NIH also warns, "Like drugs, herbal or botanical preparations have chemical and biological activity. They may have side effects. They may interact with certain medications. These interactions can cause problems and can even be dangerous. Before taking an herb or a botanical, consult a doctor or other health care provider-especially if you have a disease or medical condition, take any medications, are pregnant or nursing, or are planning to have an operation. Before treating a child with an herb or a botanical, consult with a doctor or other health care provider."
Here is the NIH fact sheet on valerian.