STANDARDIZED HERBAL EXTRACTS: AN HERBALIST'S PERSPECTIVE
BY
Dr. Michael Tierra, L.Ac., O.M.D., Founding Member of the American Herbalists Guild

The advent of herbal products in the form of standardized extracts was initiated in 1992 as a result of a European Guaranteed Potency law. Since that time, proponents have heralded standardized herbal extracts as a major historical advance, allowing both consumers and medical doctors to use herbal products with greater confidence and more consistent results. What most don’t realize, however, is that the majority of these advocates consist of:
1. academics and medical doctors who often have little personal or clinical experience with herbs,
2. researchers whose work is funded by drug companies that manufacture the standardized extracts used in their clinical trials, and
3. naturopathic physicians who have financial ties with the companies that produce these products.

One group noticeably lacking from the chorus of standardized extract enthusiasts is professional clinical herbalists who rely on herbs as their primary healing modality. While not categorically condemning standardized extracts, clinical herbalists agree that just because an herb is biochemically standardized, it is not automatically more potent or efficacious than a non-standardized extract.

Standardized Herbal Extracts – What Are They?

Standardized herbal extracts are of two main types: An active constituent extract where there is a known and accepted active biochemical principle, and a marker extract where the active biochemical principle is not known and a characteristic compound is used as a "marker," which signifies the presence of the other biochemical compounds that give the herb its therapeutic properties.

In an active constituent extract, the known biochemical compound is isolated from the herb and concentrated to an amount not naturally found in the plant. Think of caffeine from coffee or morphine from the opium poppy. This type of extract tends to be more drug-like, potentially having undesirable side effects not normally present in the herb or its non-standardized extract.

From the herbalist’s perspective, this type of extract, while stronger in intended action is more of an herbal drug or "phytopharmaceutical" as it is called in Europe. As such, when the isolate is manipulated at the expense of the whole herb’s constituents, one may lose other properties contained within the herb, as well as buffering compounds that may lessen adverse reactions.

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