History

In the UK, medical herbalism traces its historical traditions partly to Galen’s (a Greek physician of the 2^nd century AD) model of ‘bodily humours’ (blood, black bile, yellow bile, phlegm), their ‘temperaments’ (e.g. hot, cold, damp) and the belief that illness resulted from an imbalance in these humours. Herbs were used to correct the imbalance and were often described as, for example, ‘heating’ or ‘cooling’; a ‘cooling’ herb, such as peppermint, would be used to treat a ‘hot’ condition, such as fever. In the UK, herbalism has also drawn on other traditions, such as the use of herbs in North America after Samuel Thomson, although Thomson was himself influenced by herbalism in Europe.

Modern herbalism

Today, medical herbalism, practised by medical herbalists, draws on traditional knowledge, but, increasingly, this is interpreted and applied in a modern context. For example, herbalists use current knowledge of the causes and consequences of disease as well as some of the diagnostic tools, such as blood pressure measurement, used in conventional medicine. Also, there is an increasing emphasis on using evidence from modern randomized controlled clinical trials to support the traditional use of herbal preparations. Some other aspects of modern-day herbalism as seen by the herbalists are listed below:

Importantly, different constituents of a medicinal plant are seen as acting together in some (undefined) way that has beneficial effects. For example, the constituents may have additive effects, or interact to produce an effect greater than the total contribution of each individual constituent (known as ‘synergy’), or the effects of one constituent reduce the likelihood of adverse effects due to another constituent. Similarly, it is also believed that some combinations of different herbs interact in a beneficial way. There is some experimental (but little clinical) evidence that such interactions occur, although it cannot be assumed that this is the case for all herbs or for all combinations of herbs. Synergy is discussed in detail in Chapter 11.

Conditions treated

Medical herbalists treat a wide range of acute (e.g. infections) and, more usually, chronic conditions. Very often the chronic conditions are those that are difficult to treat, including irritable bowel syndrome, premenstrual syndrome, eczema, acne and other skin conditions, cystitis, arthritis, depression, chronic fatigue syndrome or migraine.

Herbalists’ prescriptions

A first consultation with a herbalist may last for an hour or more, during which the herbalist will explore the detailed history of the illness. Generally, a combination of several different herbs (usually four to six) is used in the treatment of a particular patient. Some examples of such combinations are given in Table 13.1, although there are no ‘typical’ prescriptions for specific conditions; as stated above, even patients with the same condition are likely to receive different prescriptions. Sometimes, a single herb may be given, for example, Vitex agnus-castus (chasteberry) for premenstrual syndrome and dysmenorrhoea. Each patient’s treatment is reviewed regularly and is likely to be changed depending on whether or not there has been a response.

Table 13.1 Examples of herbal prescriptions

Herbalists usually prescribe herbal medicines as tinctures, although sometimes more concentrated formulations (fluid extracts) are used. Where a prescription requires several herbs, tinctures and fluid extracts are blended into a mixture. Some herbalists will prepare their own stock material, others purchase it from specialist suppliers and most dispense their own herbal prescriptions. Other oral formulations (tablets, capsules) and topical preparations of herbs may also be prescribed.

Comparison of herbalism with rational phytotherapy

Herbalism contrasts with rational phytotherapy in several ways (Table 13.2). Importantly, the herbalist’s approach has not been evaluated in controlled clinical trials, whereas there are numerous controlled clinical trials of specific phytotherapeutic preparations. Another important difference is that, although many of the same medicinal plants are used in each of the two approaches, the formulations of those herbs are often very different. For example, St John’s wort (Hypericum perforatum L.) is used in both rational phytotherapy and by herbalists. However, in rational phytotherapy, the preparations used are likely to be extracts of H. perforatum herb (leaves and tops) standardized on hypericin content and formulated as tablets. By contrast, herbalists are likely to use a tincture of H. perforatum herb that is not standardized on its content of any particular constituent.

Table 13.2 Comparison of herbalism and rational phytotherapy

The terminology is often confusing. Herbalism is sometimes also referred to as phytotherapy, and both herbalism and rational phytotherapy are sometimes described as ‘herbal medicine’. Likewise, preparations used in rational phytotherapy and in herbalism may both be referred to as ’herbal medicines’ or ‘phytomedicines’.

In some ways, herbalism is similar to Western medicine. For example, both use drug intervention (herbs and conventional drugs, respectively) to counteract disease, although herbalism is focused on correcting disturbed function rather than treating symptoms. Both use material doses (in contrast to homoeopathy, which uses highly dilute preparations, not all of plant origin). Herbal medicine in the UK covers a wide spectrum of practice: there are traditional herbalists who refer mainly to the older traditions and philosophy, those whose view is aligned more closely with ‘modern’ rational phytotherapy, and those whose practice is somewhere between the two approaches.

Evidence of efficacy and safety

There is a significant body of clinical evidence on the potential benefits and potential risks associated with the use of specific herbal medicines (for the most important species see Part B). The vast majority of this information relates to the use of specific herbal medicines formulated as phytopharmaceuticals and used in the same manner as conventional pharmaceuticals, usually under the supervision of a physician, to treat symptoms of disease. There has been very little investigation of the efficacy and safety of herbal medicines and combinations of herbal medicines used by herbal medicine practitioners. Furthermore, the efficacy and safety of herbalism as a treatment approach has not yet been evaluated scientifically.

History

Homoeopathy was developed around 200 years ago by Samuel Hahnemann, a German physician and apothecary. His development of the principles of this controversial approach to treatment needs to be considered against the background of medical practice at the time, when the use of leeches, bloodletting, strong purgatives and emetics, and preparations containing toxic heavy metals, such as arsenic and mercury, was widespread. It is reported that Hahnemann was dissatisfied with these harsh therapeutic strategies and that this led him to give up the practice of medicine. During this period, he was stimulated to experiment with cinchona bark (which was used to treat malaria) and found that, while taking high doses of the substance, he experienced symptoms that were similar to those of malaria. Hahnemann then used this approach (which he called a ‘proving’) with healthy volunteers who were given many other substances in order to build up a ‘symptom picture’ for each substance. On the basis of his findings from these experiments, Hahnemann outlined three basic principles of (classical) homoeopathy:

Modern homoeopathy

Despite of all controversies, homeopathy has spread widely and is a very popular form of health care in many European, Asian and American countries. Hahnemann’s principles of homoeopathy still form the basis of modern homoeopathic practice, with the exception of the single remedy rule, which is ignored by many homoeopaths in favour of multiple prescribing. Today, around 1200 homoeopathic remedies are commonly used. For many of these, homoeopaths rely on Hahnemann’s provings and, therefore, guidance on which symptoms the remedies can be used to treat. Modern-day provings involving healthy volunteers are sometimes undertaken, and several have involved rigorous study design (randomized, double-blind, placebo-controlled). However, Hahnemann did not use rigorous study design, although he did specify certain criteria; for example, subjects were not permitted to have coffee during the course of a proving.

In addition to the key principles of homoeopathy outlined above, homoeopaths also claim:

In choosing a remedy for a particular patient, a homoeopath will consider the patient’s physical, mental and emotional symptoms, as well as personal characteristics, likes and dislikes. This information is then used to select the homoeopathic remedy with a ‘symptom picture’ that most closely matches that of the patient. Computerized repertories (databases of homoeopathic remedy symptom pictures) are now available which facilitate this process.