Moreover, non-pregnant adult human hepatotoxicity has been associated with short-term use (i.e., a few days to several months) of herbal preparations containing valerian and Scutellaria (commonly called skullcap).
The very limited animal and human data do not allow a conclusion as to the safety of valerian during pregnancy.
Hydrophilic extractions of the herb commonly sold over the counter, however, probably do not contain significant amounts of isovaltrate.
The chief constituent of valerian is a yellowish-green to brownish-yellow oil which is present in the dried root, varying from 0.5 to 2.0%, though an average yield rarely exceeds 0.8%.
However, some of the GABA-analogs, particularly valerenic acids as components of the essential oil along with other semivolatile sesquiterpenoids, generally are believed to have some affinity for the GABA Valeric acid, which is responsible for the typical odor of mostly older valerian roots, does not have any sedative properties.
Valeric acid is related to valproic acid, a widely prescribed anticonvulsant; valproic acid is a derivative of valeric acid.
Because the compounds in valerian produce central nervous system depression, they should not be used with other depressants, such as ethanol, benzodiazepines, barbiturates, opiates, kava, or antihistamine drugs.Oral forms are available in both standardized and unstandardized forms.Standardized products may be preferable considering the wide variation of the chemicals in the dried root, as noted above.This variation in quantity is partly explained by location; a dry, stony soil yields a root richer in oil than one that is moist and fertile.The volatile oils that form the active ingredient are extremely pungent, somewhat reminiscent of well-matured cheese.