Effects of extracts from Valeriana officinalis L. in pharmacological studies

Though several clinical studies revealed sleep improving properties of aqueous and ethanolic extracts from Valeriana officinalis L., neither the mode of action is known nor the active constituents are identified. A sedative effect, which predominantly is assumed to be responsible for efficacy, could not be demonstrated in most clinical studies or pharmacological investigations.

The therapeutic indication given in the ESCOP monograph [1] “relief of temporary mild nervous tension and/or difficulty in falling asleep“ may not only indicate a sedative but rather a tranquillizing effect of such extracts. Thus it was the aim of this study to test extracts and fractions from Valeriana officinalis L. for sedation (narcotica induced sleeping time, locomotor activity) and anxiolysis (elevated plus maze) following acute administration to female NMRI mice.

Dosages up to 1000mg/kg bw no sedation was observed, neither motility was reduced nor sleeping time increased by aqueous as well as by alcoholic extracts. On the contrary a methanolic, an ethanolic extract and a fraction derived from the latter extract clearly increased the test parameters of the elevated plus maze (percentage of time on the open arms, percentage of open arm entries) indicating an anxiolytic effect. These results suggest that the efficacy of extracts from Valeriana officinalis L. can be ascribed to their anxiolytic activity, an effect which is in accordance with the indication of the monograph.

Reference: 1. ESCOP (2003) ESCOP Monographs – The Scientific Foundation for Herbal Medicinal Products, ESCOP, Exter.