Traditionally used to treat insomnia and for the relief of anxiety and nervous tension
In Western herbalism, valerian is classified as a nervine, that class of herbs that tonifies, calms and heals the nervous system. Valerian was widely employed by Eclectic physicians for treating nervousness, restlessness and anxiety as well as insomnia., Herbalist Matthew Wood cites from Eclectic physician John William Fyfe, MD, for example, who writes that valerian's "administration often affords great relief in the high tension common to many nervous states, and in wakefulness it exerts a sleep-producing power of much value".
In terms of the medicinal uses supported by clinical data, a World Health Organization monograph confirms it as being a mild sedative and sleep-promoting agent as well as being a mild alternative sedative "in the treatment of states of nervous excitation, and anxiety-induced sleep disturbances".
A clinical trial involving 202 patients experiencing insomnia found valerian and a standard drug (benzodiazepine) tranquilizer, oxazepam, to be equally efficacious. Compared to placebo, both treatments were significantly better; 83 percent of valerian-treated patients v. 73 percent of oxazepam-treated patient rated the treatment as "very good".
Two earlier clinical trials found that valerian produced a "significant decrease in subjectively evaluated sleep latency scores and a significant improvement in sleep quality". A follow-up study by the same authors found that valerian was as effective as benzodiazepines for reducing time necessary to fall asleep. Unlike the drugs, however, valerian had no untoward effects.