A comparative study of water-alcohol preparations of St. John's wort and imported medicinal formulations containing dry St. John's wort extract, Deprim, Negrustin, and Helarium Hypericum, was performed. The total flavonoids and athracene derivatives contents were significantly different in different medicinal formulations, though the ratios between them were essentially stable (at about 30:1), with the exception of St. John's wort infusion prepared using 40% ethanol. In the case of the preparation "St. John's Wort Infusion," the greatest levels of biologically active compounds, particularly anthracene derivatives, were obtained by extraction with 70% ethanol. These studies provide evidence that Russian antidepressant medicinal formulations with chemical compositions similar to those of foreign St. John's wort preparations can be made. It is suggested that medicinal formulations based on St. John's wort be standardized in relation to the total flavonoids (in terms of rutin) and total anthracene derivatives (in terms of hypericin) contents.St. John's wort (Hypericum perforatum L., of the Hypericaceae family) is a potential source of new, effective, Russian medicinal formulations. This herb is presently used in medical practice in the Russian Federation only as an anti-inflammatory and astringent [1]. The most popular Russian St. John's wort herb preparation is "St. John's Wort Infusion" [2]. The quality of "St. John's Wort Infusion" is regulated by Pharmacopeia Article FS 42-1889-95 and Normative Document ND 42-7991-97. Quantitative analysis is performed by assaying total flavonoids by differential spectrophotometry, though this method has a number of disadvantages [3,4].At the same time, foreign St. John's wort preparations such as Deprim, Negrustin, and Helarium Hypericum have been used with success as antidepressants. The content of the main substance, dry St. John's wort extract, in these medicinal formulations, varies significantly, from 60 mg (Deprim) per tablet to 285 mg (Helarium Hypericum) per pill and 425 mg (Negrustin) per capsule. In Russia, antidepressants are not prepared from plant material, while there is an objective need for preparations with this action. This situation can be corrected by studies to improve methods for the analysis of St. John's wort herb and addressing the optimization of the production technology.The chemical composition of St. John's wort herb is known to be quite complex [5 -7]. The main active components are flavonoids (rutin, hyperoside), anthracene derivatives (hypericin and pseudohypericin), tannins, fluoroglucins (hyperphorin), essential oils, and others. Flavonoids represent the largest group of biologically active compounds (BAS) in St. John's wort herb and are responsible for most of its pharmacotherapeutic effect. At the same time, both rutin and hyperoside are quite widely distributed in plant materials. We believe that analyses based exclusively on the contents of these components does not adequately resolve the problem of standardization. The anthracene derivative...