Valerian: Background. Actions

Common Name

Valerian

Other Names

All-heal, amantilla, balderbrackenwurzel, baldrian, baldrianwurzel, fragrant valerian, heliotrope, herbe aux chats, katzenwurzel, phu germanicum, phu parvum, valeriana, wild valerian

Botanical Name / Family

Valeriana officinalis (family Valerianaceae)

Plant Part Used

Rhizome

Chemical Components

Valtrates, didrovaltrates, isovaltrates, monoterpenes, sesquiterpenes, caffeic, gamma-amino butyric and chlorogenic acids, beta-sitosterol, methyl 2-pyrrolketone, choline, tannins, gum, alkaloids, a resin. Essential oils (0.5-2%) in the plant contain the compounds bornyl acetate and the sesquiterpene derivatives valerenic acid, valeranone and valerenal.

The chemical composition of valerian varies greatly depending on such factors as age of plant and growing conditions. Processing and storage of the herb also affects its constituents, such as the iridoid esters, which are chemically unstable.

Historical Note

The sedative effects of valerian have been recognised for over 2000 years, having been used by Hippocrates and Dioscorides in ancient Greece. Over the past 500 years, it was widely used in Europe as a calmative for nervousness or hysteria and also to treat dyspepsia and flatulence. Legend has it that the Pied Piper put valerian in his pockets to attract the rats out of Hannover. Valerian was widely used by the Eclectic physicians and listed in the United States Formulary until 1946.

Valerian:  Main Actions

ANXIOLYTIC AND HYPNOTIC

Extensive pharmacological research has been conducted; however, identifying the main active constituents in valerian and their mode of action remains unclear and several neurobiological mechanisms are believed to be at work. In vitro tests so far have demonstrated that valerian stimulates the release of GABA, inhibits GABA reuptake and may have an effect at GABA receptors. There is also evidence of agonist effects at the human A1 adenosine receptor.

One clinical study using both kava kava and valerian treatment has observed anxiolytic effects; however, it is uncertain what role valerian played in producing the effect.

Both in vivo and numerous clinical studies confirm sedative activity.

ANTISPASMODIC

Both in vitro and in vivo studies provide evidence of antispasmodic activity on smooth muscle.

Valerian:  Other Actions

A pharmacokinetic study with healthy adults found that typical doses of valerian are unlikely to produce clinically significant effects on the CYP2D6 or CYP3A4 pathways of metabolism. These results were confirmed in another human pharmacokinetic study that found no evidence that valerian affects CYP3A4/5, CYP1A2, CYP2E1, and CYP2D6 activity.