Animal studies show valerian reduces blood pressure and suggest that it has anti- convulsant effects. One day it may play a role in treating epilepsy. Valerian is included in the Food and Drug Administration's list of herbs generally considered as safe, although large amounts may cause headache, giddiness, blurred vision, restlessness, nausea, and morning grogginess. The plant is found throughout Europe and northern Asia, and is common in England in marshy thickets and along ditches and rivers, where its tall stems may generally be seen in the summer towering above the usual herbage. Other members of its family include spikenard and Jacob's ladder.
Medicinal valerian is a hardy perennial that reaches about five feet.
Its medicinal roots consist of long, cylindrical fibers from its rhizome. Its stem is erect, grooved, and hollow, and its leaves are fernlike. Valerian's white, pink, or lavender flowers develop in umbrella-like clusters, blooming from late spring through summer. It may be propagated from seeds or root divisions. Thanks to Andi Metcalfe for this report on valerian.