Standardized Extracts
© Chanchal Cabrera MSc, MNIMH, AHG

Traditional herbal medicines include teas (infusions and decoctions), tinctures, poultices and salves. Recently we have begun to make increasing use of tablets and capsules. These are all relatively simple preparations, not highly processed and readily available at very reasonable cost.

Herbal medicine has traditionally been a medicine inherently ‘of the people, for the people, by the people’ and this is an important distinction between folk healers and allopathic medical doctors. Herbal medicines have always been applied by housewives and mothers as well as by professional clinical herbalists, lay healers and midwives. There is an inherent democracy in this ready availability of herbal medicines - it is non-hierarchical and egalitarian. It is reflective of the intrinsic safety of traditional herbal medicines, given to us by empirical knowledge handed down through millennia from generation to generation and tested again and again on human bodies under all sorts of circumstances. Although herbalism was repressed and refuted, and often branded witchcraft, down through the ages, the knowledge was never quite lost and, indeed, was continually being added to by empirical learning and through apprenticeship

Reductionist scientific orthodoxy has held sway for only about 100 years and it is only 50 years since the advent of modern pharmaceutical science with the myriad of petrochemical-based drugs we know have. This short time has been long enough, however, for millions of ordinary people to realize that most modern pharmaceuticals do not cure the diseases for which they are prescribed and, furthermore, are responsible for a staggering percentage of all hospital admissions.

The public has been hugely disillusioned and they are turning in ever bigger numbers to natural health care products and services. In response the last decade or so has seen the increasing interest of large multinational pharmaceutical companies in herbal medicines. The impact of reductionist science and commercial interests on traditional medicines has resulted in an entirely new form of medicinal product being created - the standardized extract.

This type of product is made by refining and concentrating certain constituents to a specified percentage and sometimes discarding the majority of the plant material to make room in the capsule for the required amount of the specified "active compound". This concentration may be achieved using various solvents and often requiring heat to evaporate away any toxic residues. The end result can be measured and precisely calibrated for exact percentages of constituents. This is considered desirable because it conforms to the requirements of scientific rigor in performing the double blind cross over placebo controlled clinical trial. The standardized extract is a highly processed product, not at all similar to a traditional herbal remedy and more akin to a botanical pharmaceutical.

There are many areas of concern when reviewing the efficacy and safety of standardized products and the results of the trials which use them:

1) So-called active constituents, isolated or synthesized, are not necessarily relevant when reviewed in the context of the whole plant remedy. Tests of function and safety of an isolated constituent may not be applicable to the whole plant. Eg. Salix spp. (Willow) has far higher analgesic and anti-inflammatory powers than its quota of salicylates would suggest and the toxicity of ephedrine is far higher than that of the whole plant Ephedra.

2) In many, if not most cases, tradition and experience tell us how to use a plant but we rarely know what is chemical is actually responsible for a certain action. Where attempts have been made to identify the active constituent, they invariably fail. An example of this is Valerian (Valeriana off.) in which it was thought for some time that the valepotriates were the active component and it was later discovered that there was a marked and observable relaxant effect from Valerian even with the valepotriates removed. Back to the drawing went the marketers to find another angle with which to differentiate their product from the next one on the shelf.

3) Using animal models to research new medicines may not provide useful or relevant data for the use of such medicines in humans. Many chemicals which are found to be harmless to animals are nevertheless toxic to humans. Eg. Thalidomide was extensively tested on guinea pigs before being declared safe for public consumption.

4) Many environmental toxins (pesticides, dioxins etc.) are fat soluble and will tend to concentrate in the lipid components of plant cells. These will be easily dissolved into a solvent (which itself may be a toxin such as hexane, acetone, dichloromethane or benzene) and both exogenous toxins and solvent residues may contaminate the end product. Heating the treated plant material may remove some or most of the solvent residues, but is damaging to the plant cell constituents (eg. Enzymes and proteins are denatured by heat) and will evaporate away any volatile oil fragments which are themselves often highly medicinal.

5) Clinical trials in the classical scientific model are not statistically significant when compared to the hundreds of centuries of empirical knowledge and the experience of clinical practitioners. The traditional healer works with so many sensory and extra sensory perceptions attuned to the differentiating qualities of the patient that no two people will ever receive the exact same treatment protocol. Of course there are similarities and general themes that are frequently incorporated into formulas, and these may form the basis of the modern market for herbal products, but in a professional consultation the details and precise proportions of components in each individual formula are unique each time.

6) Almost all the research being done into single plant ingredients is funded, directly or indirectly, by those with a vested financial interest, a stake, in selling a product. Research endowments to universities, independent laboratories and rainforest research are all being funded by pharmaceutical corporations and they are all looking for a molecule or a process they can patent and thus make money off. Thus the drive toward standardization may be impelled more by a desire to make money than a desire to heal people or to understand herbal medicine.


The effect of the trend toward standardized medicines is to make herbals products less and less available to the average person. The public is led to believe that standardized products are somehow better than Nature can make them and are more desirable than the simple plant remedy. The degree of technology applied to the botanical agents causes the price to increase dramatically and in order to convince people to spend so much money on a health product there is a need for a slick advertising campaign which costs more money and so the spiral goes.

The question we must ask is whether this is useful or appropriate? Who really benefits by this technological approach to herbs? Are the standardized products really all that much better than traditional remedies? Are we in danger our losing our ‘roots’, of losing touch with the earth-centeredness of traditional medicines?

Certainly it is necessary for the herbal products industry to ensure that basic hygiene and safety standards are applied in the manufacturing of herbal medicines. Certainly there needs to be a system to control access to certain potentially dangerous herbs (Atropa belladonna, Convalleria majalis, Aconitum napellus and others). Perhaps such herbs should also be made to a guaranteed potency where specific key constituents are known to be of a certain percentage to facilitate safe dosage.

Several organizations have already begun work on creating safety systems for the use of medicinal herbs. The American Herbal Products Association has recently published a toxicology and relative safety listing for botanicals and the writing of an American Herbal Pharmacopeia is well underway and the University of Exeter in England is spearheading a toxicology reportage data base available through the Internet.

I do believe that there may be a role for standardized extracts where toxicity is an issue and possibly for inclusion in clinical trials where such precise calibrations are required for credibility, but I also believe that the very principle at issue here is that standardization is reductionist not holistic. Standardized extracts are usually a case of the emperor having no clothes - newer isn’t always better.

It is my belief that one of the roles of the modern day herbalists is to maintain the simplicity and naturalness of our heritage and to ensure that it always remains readily available to the people. While safety is always of paramount importance, we must be extremely careful to preserve our empirical knowledge of traditional whole plant medicines. The more the natural world is desecrated and destroyed, the more urgent it becomes that the herbalists and traditional healers preserve their cultural heritage and hence their relationship with the Earth.