General Description
Common valerian is a perennial plant that reaches up to 1.5 meters
in height. Native to Europe and Asia and naturalized in North America,
valerian has an erect, grooved stem that bears four to eight pairs
of leaves. Each leaf is made up of seven to ten pairs of toothed
leaflets, which are usually 5 to 7 centimeters long. The plant flowers
from June to August, bearing clusters of small, pinkish-white blossoms.
The fruit is a pale brown, oval-shaped capsule, containing a single
seed. Valerian has a short, thick, yellowish-brown root, which is
used for therapeutic purposes.
Health Applications
History and Traditional Use
Valerian root has a history of medicinal use dating back over
2,000 years. It appears in the writings of ancient physicians
Dioscorides and Pliny, who prescribed it for a wide variety of
internal and external applications, as did the 17th century British
herbalist Nicholas Culpeper.1 The root was
used as bait by rat-catchers, and the legendary Pied Piper of
Hamelin was said to have employed it to lure rats from the village.2
Modern use of valerian root centers on its mild sedative properties.
Chemical Composition
Valerian contains a number of active compounds, including valepotriates,
valerenic acid, lignans, sesquiterpenes, and monoterpenes; all
of which may contribute to the herb's sedative effect.3
However, the valepotriates are unstable and rarely present outside
of the fresh root. Valerian extracts are often standardized for
valerenic acid content.
Insomnia
Germany's Commission E has approved valerian root for treatment
of restlessness and sleeping disorders based on nervous conditions.4
A number of trials have found valerian to be effective for treating
insomnia,5-8 and one trial found a valerian-hops
preparation to be as effective as the prescription sedative benzodiazapine,
but with fewer side effects.9
Dosage/Toxicity
Germany's Commission E recommends 2-3 grams of dried valerian
root (or extracts providing the equivalent) several times per
day, and there are no known side effects at this dosage.4
Mild, transient symptoms of toxicity have been reported in a patient
taking approximately 20 times the recommended dose.10
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