Valerian wallichii (Amantila)
Valerian wallichii (Amantila)      Commonly known as Tagar, Valerian is widely used to treat insomnia and anxiety. Preliminary data from several human trials suggest that valerian improves subjective measures of sleep quality and sleep latency. Better effects have been noted in poor sleepers. Early evidence suggests that ongoing use may be more effective than acute (single-dose) use, with progressive effects over several weeks. However, most available studies have been methodologically weak, and in most cases results have not been confirmed using objective sleep pattern data in a sleep laboratory or validated measurement scales.      Valerian root may contain as many as 150 compounds, not all of which have been thoroughly investigated. The known major constituents are the valepotriates (irioid compounds such as valtrate and related analogs), volatile oils (monoterpenes, sesquiterpenes, esters of valerianic and isovaleric acid), kessanes, valerenal, valeranone and valerenic acid (cyclopentane sesquiterpenes). Its well-known medicinal and pharmacological activities include:      Anti-depressive effects: Muller et al. conducted an open, multicenter study to investigate the effectiveness of a combination therapy of St. John's wort extract and valerian extract for depressive disorders in comorbidity with anxiety disorders.The authors note that the combination therapy was well tolerated, and no significant side effects occurred. An ethanolic extract of Japanese valerian root and a-kessyl alcohol derived from a methanol extract of Valeriana fauriei exerted activity in a mouse model of antidepressant activity.      CNS effects: The flavonoid glycoside linarin, flavone 6-methylapigenin, and flavanone glycoside 2S (-) hesperidin have been suggested as possessing anxiolytic or sedative properties. It is possible that a combination of compounds impart clinical activity to valerian. Extracts of valerian and some of its components have been shown to have effects on gamma-amino-butyric-acid (GABA) related mechanisms in the CNS, exerting potential activity at both pre- and post-synaptic sites. Valerian extracts can alter binding at benzodiazepine receptors and GABA-A (muscimol) receptors. Extracts have been reported to increase synaptasomal GABA concentrations, possibly by enhancing GABA release and inhibiting GABA uptake.      Hypotensive effects: In anaesthetized guinea pigs, orally administered Valeriana officinalis L. root ethanolic and aqueous extracts (50, 100 and 200mg/kg) demonstrated significant anticoronaryspastic and antihypertensive effects against pitressin-induced coronary spasm and pressor response, similar to that exhibited by nifedipine Safety Profile      Likely safe: When used orally at recommended doses (400-600mg of aqueous or aqueous-alcoholic root extract per day) by otherwise healthy adults for short or intermediate-term use. Valerian root is widely reported as being safe in recommended doses for brief periods of time      Valerian should be discontinued two weeks before elective surgery, due to a risk for increased bleeding, and it should be avoided during the perioperative period. Valerian should not be taken while driving or operating heavy machinery due to the risk of sedation or reduced vigilance, although there is controversy in this area. Herb Drug interactions      Antidepressant agents, monoamine oxidase inhibitors (MAOIs): Based on animal and human studies, valerian may increase the amount of the effects and side effects such as drowsiness caused by antidepressants, although this is an area of controversy      Antidepressant agents, selective serotonin reuptake inhibitors (SSRIs): Based on animal and human studies, valerian may increase the amount of the effects and side effects such as drowsiness caused by antidepressants, although this is an area of controversy      Sedatives: Based on animal and human study, valerian may theoretically potentiate the effects of CNS depressant drugs, although studies in humans taking CNS-active medications concurrently with valerian have not revealed an increased rate of adverse effects. Short term impairments in vigilance and concentration, as well as mild fatigue, have been reported in trials; residual sedative effects appear to be less pronounced than those associated with benzodiazepines. Selected relevant published references • Planta Med. 1985;(1):28-31. • Biol Pharm Bull. 2007;30(2):363-366 • Pharmacotherapy 2000;20(5):568-574 • Pharmacopsychiatry 1988;21(6):447-448.