Anxiety disorders, including generalized anxiety disorder (GAD), panic disorder, post-traumatic stress disorder (PTSD), and obsessive compulsive disorder (OCD), are the most prevalent behavioral disorders in the United States, affecting 17.2% of the population (Somers et al. 2006). The use of herbal supplements to treat anxiety and insomnia has been increasing and the mechanisms of action of several are being elucidated.
Valerian, derived front the Valeriana officinalis plant, is one of the most popular herbal supplements for the treatment of anxiety and insomnia. In spite of its large popularity, scientific research on the efficacy of valerian as an anxiolytic is relatively sparse. Of the literature available, the emphasis has been on its activity on y-amino butyric acid (GABA) neurons within the central nervous system. For example, Awad et al. (2007) found that an ethanolic extract of Valeriana officinalis prompted increased brain GABA levels and neurotransmission by stimulating glutamic acid decarboxylase (GAD) in rat brains, as measured by an in vitro enzyme assay. Further, extracts from valerian root facilitated the inhibition of GABA transanminase activity, the enzyme responsible for breaking down GABA, also measured by an in vitro enzyme assay.