Nature offers a vast pharmacopoeia of remedies medical science has at last begun to explore – taxol, for example, one of most powerful agents against cancer, is a substance found naturally in the Pacific yew tree. But despite the range of natural remedies at our disposal, it is of great concern that much of this vital armoury against disease is under threat just at the moment when more people are beginning to recognise its value.
In deriving drugs from plants, pharmaceutical processes tend to isolate and synthesise the active ingredient for the condition they wish to treat. The result, as with taxol, can indeed be life-saving but, in isolation, a specific chemical ingredient may produce side-effects that other constituents in the plant would normally help to counter-balance. For example, meadowsweet, a plant traditionally used to treat digestive disorders, contains salicylic acid, the basis of aspirin. On its own, salicylic acid can cause internal bleeding (as aspirin does in people with sensitive stomach linings), but in meadowsweet there are other chemicals, tannin and mucilage, that protect the stomach.
Traditional herbal remedies are extracted from leaves, flowers and other parts of a plant and contain a complex mix of active ingredients to provide the therapeutic effect. Medical herbalists, who make up their own preparations from combinations of fresh or dried plants, believe that this mix within individual herbs as well as in traditional mixtures of plant medicines creates what is called synergy, in which all the chemical components contribute to the remedy’s specific therapeutic effects.
Herbal remedies are one of the most widely used forms of complementary medicine, the popularity of which continues to grow. With so many people turning to complementary medicine, often in addition to orthodox treatment, the House of Lords Report on Complementary and Alternative Medicine in 2000 rightly recommended better regulation and research of such therapies so that both patients and the medical establishment can have confidence in their efficacy and safety.
This recommendation for better regulation included the regulation of herbal products that are manufactured and sold over the counter as pills, capsules, lotions, creams and tinctures – a market estimated to be worth about £126 million a year. Although regulation of this area is necessary, it is controversial, as the current campaign against the proposed European Directives on herbal medicines and on vitamin and mineral supplements demonstrates. Thanks in large part to the internet, and an increasing number of articles in the media, the public is increasingly familiar with health matters which makes the need to achieve a delicate balance between regulation and risk-avoidance, and genuine patient choice, all the more desirable.
Since 1968, most herbal remedies have been exempt from the requirement to have a full medicine licence, and have been virtually un-regulated as regards their quality and safety. Once the new Directive on herbal medicines becomes UK law (sometime around 2009), it will require manufacturers to register unlicensed products and produce them according to ‘good manufacturing practice’, with a guarantee that herbal remedies conform to a uniform standard. They will also have to demonstrate that products have been safely used for 30 years in the European Union or, in the case of herbs from outside the EU, for a combination of 15 years within the EU and 15 years outside it.
Of course, I recognise – and welcome – the benefits that may emerge from this proposed new regulation and the protection it should offer consumers. I hope, however, that the standards set to assure the safety of herbal medicines will respect their history of traditional usage and not impact adversely on their future availability to the public. Further, it is important to note the anxiety being expressed by many practitioners with regard to the ability of the Medicines And Healthcare Products Regulatory Agency (the new title for the Medicines Control Agency) to keep licensing costs and red tape to a minimum to avoid damaging the many excellent small businesses in the herbal sector.
It is heartening to learn that the European Commission has just rejected amendments proposed by the European Parliament calling for herbs to be classified as medicines according to their `pharmacologically-active levels’. It is important that this rather rigid way of defining medicines does not replace the current more flexible EU definition of what constitutes a medicine during the process of re-evaluating EU medicines law currently in progress. This could lead to numbers of medicinal herbs being reclassified as foods because knowledge of their pharmacologically active ingredients is insufficient to provide evidence of medicinal use. Such re-categorising might have safety implications as some herbal medicines might be marketed as foods. Moreover, this emphasis on active pharmacological ingredients may lead to the artificial enhancement of perceived active constituents in plant medicines, ignoring the natural chemical balances asserted by the traditional concept of synergy.
We simply do not know enough yet about how these naturally occurring constituents interact, as we saw recently with the herb, St. John’s Wort, which is often used to treat mild depression. The risk of light sensitivity, an occasional side-effect of the herb, rose when levels of a component called hypericin were synthetically enhanced in the mistaken belief that this would increase its anti-depressant effect. Yet subsequent research showed that hyperforin, another chemical that is present in much smaller quantities, is the real key to the herb’s capacity to relieve depression.
The current situation with kava-kava would seem to bear this out and provides an interesting case study. A limited number of cases of liver damage have been attributed to this herb, which is used as a natural tranquilliser. On the recommendation of the Committee of Safety of Medicines, its use has now been banned (albeit with a review in two years). But, as Professor Edzard Ernst from Exeter University points out, after five centuries of traditional use throughout Polynesia, as well as more recent years of worldwide application, the risk of liver damage from kava-kava is no worse than that associated with Valium (Diazepam).
Scientists working in complementary medicine state that kava-kava has none of the addiction problems of the conventional tranquilliser, nor the side-effects associated with Valium and other benzodiazepine-based drugs. Some believe the recent problems may well be due to industrial extraction techniques used in producing Kava-Kava which, in increasing the concentration of active constituents called kavalactones, have removed other important components that protect the liver. Prohibition could have the unfortunate result of stifling further research into what many agree is a potentially valuable treatment.
The demand for herbal medicines has another aspect. At a time when farmers everywhere are struggling to make ends meet, the development of a natural pharmacy of organically grown herbs offers an alternative means of earning a living. Yet without protective measures, herbs are easily adulterated or their quality compromised. The North American herb, black cohosh, widely used by women because it contains compounds that mimic oestrogen, is becoming scarce and expensive. In the United States where it grows wild, itinerant pickers strip the harvest and destroy its habitat. Meanwhile, modern farming methods and rampant deforestation in Asia and the Amazon basin threaten traditional herb crops whose significant medical potential researchers are just discovering. The South American herbs Pau d’Arco and Cat’s Claw are under investigation for anti-cancer and immunity-enhancing properties at the very time their survival is endangered.
Research is desperately needed into herbs and their actions. At the moment bio-scientists admit they are at the ‘don’t know’ stage in determining which of 20 or more ingredients in a plant are the active ones, or even what they do. Of course, herbal medicine is only part of the picture and, along with all those working through my Foundation for Integrated Health, I am acutely aware that the good quality evidence to support claims of efficacy for all forms of complementary medicine is essential.
My Foundation for Integrated Health funds a small research programme, but also encourages large research charities and funding organisations to invest in this area as a priority. I am delighted that the Government’s five-year programme of research in complementary medicine, with which we are actively involved, is due to commence this autumn (2003) with £7.5 million funding. Inevitably, some therapies will be found to be ineffective, but even negative outcomes are important, acting as markers in steering us towards a more integrated healthcare system.
Already one of my Foundation’s own studies has borne fruit. A clinically-controlled trial led by Dr Chloe Stallibrass at the University of Westminster and published in Clinical Rehabilitation last year (2002) has shown that the Alexander Technique can help relieve some of the distressing symptoms of Parkinson’s disease. Researchers elsewhere have found that acupuncture, for example, can relieve back pain, nausea and vomiting, migraine and dental pain. There is solid evidence to support the use of Saw Palmetto berries for prostate problems, hawthorn extract for heart failure, the nutritional supplement glucosamine for osteoarthritis – the list is growing. In December 2002, the British Medical Journal reported that aromatherapy and light therapy helped relieve agitation, sleep disturbance and other behavioural and psychological symptoms of dementia in the elderly.
While the vast majority of people clearly do not want to forego orthodox medicine, the growth in popularity of complementary medicine – frequently at the patient’s own expense – suggests that most of us prefer the option of both kinds of approach wherever possible. Most health professionals would agree that there are significant gaps in the ability of orthodox medicine to treat a wide range of chronic diseases, such as arthritis and irritable bowel disease.
So it seems to me only logical that the NHS should offer both the orthodox and the complementary under one-roof as part of an integrated approach to health and care. Indeed, some NHS Health Centres are already doing this. Patients in such centres with migraine, for instance, may receive orthodox advice and treatment from their GP and then be referred for a session with an acupuncturist down the corridor. The patient may feel safer because his or her GP, who may have been known and trusted for several years, is part of such an integrated approach. It has to be better and safer than the current system where too many patients see complementary practitioners without seeing their GPs.
Many say that effective modernisation will require the NHS to be courageous and innovative. If most patients and many GPs want to see an NHS that provides integrated health and services with greater choice, then building a truly patient-centred NHS – offering both orthodox and complementary healthcare as the norm – might be the next courageous thing to do. And, who knows, moving towards a truly patient-centred NHS might just do much to take the pressure off the currently hard-pressed NHS and substantially help reduce the Nation’s drug budget…?