Valeriana officinalis is a perennial herb with large pinnately compound leaves and numerous small pink flowers. The widespread genus Valeriana includes about 200 species, many of which have been used medicinally; V. officinalis is one of about 20 species native to Europe, and is frequently cultivated. The small vertical rhizome and roots, which are known for smelling unpleasant when dried, are used in traditional medicines. There are three subspecies, one of which spreads by narrow stolons, or creeping stems, which are used along with the root. Teas or tinctures of valerian root have for many centuries been used as a mild sedative and sleep aid, and until recently as an anticonvulsant to treat epilepsy. During World War II, valerian was reportedly often recommended by physicians in Britain, where shortages of pharmaceutical drugs occurred.

Multiple classes of compounds, including sesquiterpenes (valerenic acids, etc.), valepotriates, and baldrinals (decomposition products of valepotriates), contribute to valerian?s activity. Though bioactive in lab studies, valepotriates are rapidly degraded and not very bioavailable, so that consumer products provide a very low dose of those compounds. Human studies have been relatively few and their results have been mixed, although both animal studies and several large human trials have shown activity; weeks of treatment and a reasonably high dose may be needed for best results. Two human studies have directly compared valerian to oxazepam for insomnia and found similar efficacy. Valerian has little toxicity even at excessive doses. A handful of claims of liver disease associated with valerian use involved individuals who were taking herbal products containing multiple plants including skullcap, which is known sometimes to be contaminated with the hepatotoxic plant germander; there is no rational reason to assume that all of the other plants in that product were also hepatotoxic. The only readily available animal study to examine the safety of valerian use in pregnancy used a valepotriate mixture rather than a complete extract; therefore, safety in pregnancy has not been adequately demonstrated and further studies would be desirable.

Selected References

Bell, C. D. 2004. Preliminary phylogeny of Valerianaceae (Dipsacales) inferred from nuclear and chloroplast DNA sequence data. Molec. Phylogenet. Evol. 31:340-350.

Donath, F., S. Quispe, K. Diefenbach, A. Maurer, I. Fietze, and I. Roots. 2000. Critical evaluation of the effect of valerian extract on sleep structure and sleep quality. Pharmacopsychiatry 33:47-53.

Evstatieva, L. N., N. V. Handjieva, S. S. Popov, and P. I. Pashankov. 1993. A biosystematic study of Valeriana officinalis (Valerianaceae) distributed in Bulgaria. Pl. Syst. Evol. 185:167-179.

Herrera-Arellano, A., G. Luna-Villegas, M. L. Cuevas-Uriostegui, L. Alvarez, G. Vargas-Pineda, A. Zamilpa-Alvarez, and J. Tortoriello. 2001. Polysomnographic evaluation of the hypnotic effect of Valeriana edulis standardized extract in patients suffering from insomnia. Planta Med. 67:695-699.

Houghton, P. J. 1999. The scientific basis for the reputed activity of Valerian. J. Pharm. Pharmacol. 51:505-512.

Leathwood, P. D., F. Chauffard, E. Heck, and R. Munoz-Box. 1982. Aqueous extract of valerian root (Valeriana officinalis L.) improves sleep quality in man. Pharmacol. Biochem. Behav. 17:65-71.

Ockendon, D. J. 1976. Valeriana. Pp. 52-55 in: T. G. Tutin et al., eds. Flora Europaea, vol. 4. Cambridge University Press: Cambridge.

Ziegler, G., M. Ploch, A. Miettinen-Baumann, and W. Collet. 2002. Efficacy and tolerability of valerian extract LI 156 compared with oxazepam in the treatment of non-organic insomnia ? a randomized, double-blind, comparative clinical study. Eur. J. Med. Res. 7:480-486.