Pharmaceuticals hypericin

St. John s wort and some individual constituents of the preparations have been administered orally, topically, and intravenously in various pharmaceutical formulations, including tinctures, teas, capsules, purified components, and tablets. These botanical preparations of St. John s wort are prepared from plant components (i.e., flowers, buds, and stalk) whose content of the wide array of structurally diverse bioactive constituents may differ (Table 1 and Fig. 2). Many commercial tablet and capsule formulations of St. John s wort are standardized using the ultraviolet absorbance of the naphtho-dianthrones, hypericin, and pseudohypericin, to contain 0.3% hypericin content. Thus, a 300 mg dose of St. John s wort contains approximately 900 pg hypericin per dose. Despite the standardization of dosage forms... 

Commercially available St John s wort is not prepared following rigorous pharmaceutical standards and wide variations in concentrations of active ingredients have been reported. One report involving the determination of hypericin and hyperforin content among eight... 

Moreover, a complete characterization of all the chemical constituents from a natural product is often unknown. Unlike pharmaceuticals, botanical products are complex mixtures in which the active ingredients may be unknown or only partially characterized. For several herbal products, the active ingredient or the quantity necessary for effectiveness has not been determined. For example, some manufacturers standardize St. John s wort according to its hypericin content, which is only 1-10 identified active components in this herb. Additionally, the chanical makeup of a natural product may vary depending on the part of the plant processed (stems, leaves, roots, etc.), seasonality, and growing conditions. ... 

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