August 2010

According to a review of clinical trials of herbal medicine (Guo, Canter and Ernst 2007) there is no scientific evidence for the efficacy of herbal medicines tailored to suit the individual. 

Flaws in the methodology, however, prevent this study from being valid as sufficient evidence to discount the use of tailored remedies in western herbal medicine. 

·         Only three studies were critically evaluated and only one of these was a study of individualised western herbal medicine.  The other two were of Chinese and Ayurvedic medicine, both of which have a different approach to each other and to western herbal medicine. 

·         This one study of western herbal medicine was for treatment of osteoarthritis of the knee.  There were only 20 individuals enrolled in the study and results were drawn from only 14 who finished the trial, a participant number far too small for any conclusions to be drawn from it.  Furthermore, as all participants continued with their orthodox painkillers and anti-inflammatory drugs for the duration of the trial it would have been difficult to ascertain whether the herbal remedies were having an effect on the patients’ discomfort.

·         Considering that around 0.9% or 540,000 of the UK population people visit western medical herbalists annually (Thomas et al. 2001) for a vast array of conditions, many of which are suffered from concurrently (hence the individualised remedies) citing only one condition does not reflect the reality of a visit to a medical herbalist.

Additionally, the authors of the study are scaremongering when they suggest that individualised remedies are dangerous and may have interactions with conventional drugs.  This is potentially true but a major purpose of a four year scientific degree course  is to ensure that graduates in herbal medicine are aware of potential herb-drug interactions.  Conversely, it is potentially unsafe to self medicate with over-the-counter preparations as not only are these are from a wide variety of sources and produced by various extraction methods but also there is no guarantee that a person who is self medicating will be aware of possible interactions with any drugs they may be taking.

Western medical herbalists are well studied on the science of herbal medicine as natural pharmaceuticals (pharmacognosy).  It is this knowledge of the pharmacological actions of the phytochemicals  in each individual herb that forms the basis of the multitude of combinations that can be made up for an individual remedy, depending on the combination of conditions being treated.

Considering the hundreds of herbs, each with its own unique assortment of chemicals, used by hundreds of practitioners on thousands of patients, it is hardly surprising that there are few relevant studies of individualised remedies.  Imagine the number of possible combinations of herbs in a remedy.  Trying to plan large, controlled clinical trials with gold standard methodology would be like trying to plan the winning combination of numbers for a lottery ticket.  Also, although the actions of many plant constituents are known there are still a number that are not.  For those plants that have not yet been studied in depth in modern science there is a wealth of anecdotal evidence to support the efficacy of herbal medicine over thousands of years of use.

References:

Guo R, Canter P H & Ernst E (2007) A systematic review of randomised clinical trials of

individualised herbal medicine in any indication. Postgraduate Medicine Journal 83, 633–637.

Thomas KJ, Nicholl JP & Coleman P (2001) Use and expenditure on complementary medicine in England: a population based survey. Complementary Therapies in Medicine 9, 2-11.

To see the original paper by Guo, Canter and Ernst, click here