Valerian, in pharmacology and herbal medicine, is the name of a herb or dietary supplement prepared from roots of the plant, which, after maceration, trituration and dehydration processes, are packaged, usually into capsules. Based on its pharmacological mode of action, valerian root has been demonstrated to possess sedative and anxiolytic effects.[1]The amino acid valine is named after this plant..this is from wikipedia

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Valerian Dosing

Anxiety: Valeprotriates 150 mg/day in 3 divided doses for 4 weeks has been used in a clinical trial. Other trials used the dried herb 0.5 to 2 g, extract 0.5 to 2 mL, and valerian tincture 2 to 4 mL for anxiety. Insomnia: Valerian extract 400 to 600 mg/day taken 1 hour before bedtime for 2 to 4 weeks has been used in clinical trials. Single-dose studies have consistently found no effect for single doses of valerian in insomnia....from Drugs.com