Positive Health Online

The purpose of Herbs for the Mind is to give people the information required to make an informed decision about whether to take four herbs: St Johns Wort (Hypericum perforatum) in depression, Valerian (Valeriana officinalis) in sleeplessness, Kava Kava (Piper methysticum) in anxiety and Ginkgo (Ginkgo biloba) for deterioration of mental powers in stress or in old age.

It gives a useful summary of the published material on each herb and discusses a wide range of questions which people may ask in order to make a personal choice. It is more thorough than the average self-help book, is exceptionally well-referenced and includes a detailed discussion of dosage, labelling, possible side-effects and an overview of when each herb would be suitable.

The discussion of herb-drug interactions is less complete and less well-referenced than other aspects of the book.

One of the co-authors is principal investigator in the current US National Institute of Health randomized controlled trial of efficacy of St Johns Wort in depression. Both authors run the Anxiety and Traumatic Stress Program at Duke University Medical Center. It may be this clinical background which enables the authors to combine a good discussion of anxiety and depression for the lay person with a clear description of some of the underlying physical processes and the methods by the relative effectiveness of treatments is assessed. This means that the book would also be of use to health care professionals seeking an overview of the use of these four herbs.

Throughout the book, the authors advocate the use of standardized tablets and argue that the dose is therefore predictable. In common with many herbal practitioners, I disagree with this approach because by changing the concentrations the action of the product may be different from that of the whole plant. The difficulties which have arisen over the standardization of St Johns Wort illustrate my argument. Tablets are standardized on concentration of hypericin which is the constituent most likely to cause the rare but irritating light-sensitive rash. Hypericin is not now thought to be the main active constituent but before manufacturers hurry to standardize on hyperforin, which has been proposed as the main active constituent, they may want to be aware of new research suggesting that this constituent may be involved in the interactions between St Johns Wort and orthodox drugs. I prefer to use extracts of the whole plant. Concentrations will vary but then of course people vary as well in response to medicines. From the angle of safety, the main requisite is to ensure correct identification of plant material and consistent quality control procedures.

The book is completely geared to the situation in America where, amongst other differences, cost and availability of health care are bigger factors than in Britain. The differences affect both the tone and content of the advice. For example, the authors appear to advocate a greater use of tranquillizers than would now be considered advisable in Britain. In Britain, people are free to consult their general practitioner without fee and thus are less likely to self-diagnose if not less likely to self-prescribe. Unfortunately the authors mainly equate use of herbs with self-prescription whereas in Britain, it is possible to obtain qualified care for problems which are too complex for self-prescription. In Britain it is possible to visit a trained, qualified herbal practitioner. Members of the National Institute of Medical Herbalists take a detailed medical history, make an individual diagnosis and prescribe as appropriate for the individual.

To conclude, this book achieves what it sets out to do in that it gives the information necessary for informed decision-making. However, people in Britain have more choices in seeking professional advice and some aspects of the book are less relevant here. Although it is the enormous increase in usage of herbal medicines in America which is fuelling their increased popularity, we must remember that we have a long tradition of effective professional usage of medicinal herbs in Britain.