research aims at establishing a baseline against which products can be measured. As mentioned previously, commercially available products are not well standardized. Nor has there been a systematic determination of the optimal dose, schedule or the method of administration. In addition, the frequency and extent of drug reactions are usually unknown.[xvii] All these factors must be established before large-scale trials can begin, although some herbalists have claimed that scientists are so completely committed to western medicine they are not really interested in botanical remedies. That, of course, was one of the reasons that NCCAM was set up in the National Institutes of Health.
In Europe, the amount of research on herbal remedies depends on the country and Germany leads the way. If research on plant-based remedies takes place in the US and UK, each active ingredient must be separately investigated, which is another reason why trials are so expensive and time-consuming. But in Germany a plant-based remedy does not have to be evaluated for each known active ingredient that it contains; it can be evaluated as a whole plant. Hence most research on herbal remedies is carried out there. Another reason for a high level of research activity is that part of the cost of herbal remedies (called phytomedicines) is covered by government health insurance, and eighty per cent of doctors regularly prescribe these for their patients. Therefore, German suppliers are required to provide evidence of quality, safety and efficacy. Evidence may include empirical medical findings or personal experience, as well as findings from controlled clinical studies. A monograph is published for each plant. This lays down the safety and efficacy criteria that become the basis of licensing decisions.
Evidence of traditional use is sufficient to allow the sale of an herbal remedy in France, whereas other pharmaceuticals are subject to strict controls. The same applies to over-the-counter herbals in the UK, although the European Union is trying to introduce laws that will be common to all members. Where ancient herbal medicine continues, in such countries as the People’s Republic of China and India, herbal preparations are considered traditional medicine and exempt from the tests required for other drugs.
It is often claimed that ‘traditional use over many centuries’ means the medicine is safe. This is not necessarily true. One compelling reason is that many forms of possible toxicity, such as carcinogenicity or interactions with modern drugs, were unknown to previous generations.[xviii]
Consumers who want to avoid manufactured products in favour of more ‘natural’ products should be aware that the terms ‘non-pharmaceutical’ or ‘natural’ do not necessarily mean a product is harmless. As a rough rule of thumb, any drug that is powerful enough to have an effect is probably capable of doing harm. The very reason prescription drugs are so tightly controlled, and well researched, is that they are powerful enough to produce serious side effects. For example, in 1997 the US FDA banned or restricted eleven popular drugs because doctors ignored safety warnings or prescribed them inappropriately. If you are self-medicating be warned—follow the instructions for use and do not overdose—more is not necessarily better.
Much of this discussion on self-medicating has dwelt on the negative aspects because these are usually only talked about when some disaster occurs. Most of the time, we just take our OTC medicines trusting that all is well. Yet OTC preparations are not always benign, or free from side effects. Their safety and efficacy are not guaranteed just because they are considered ‘natural’ or because they have had centuries of traditional use. As we have already seen, the belief that dietary supplements are always harmless is erroneous—incorrect processing or substitution can cause safety hazards and an incorrect dosage can lead to unwanted effects that are quite serious.
On a more positive note, OTC medicines are generally both gentle and safe. After all, they are intended for the self-treatment of minor ailments or health maintenance. Provided they are properly processed or manufactured, there are relatively few reports of serious adverse reactions compared to those for prescription medicines. In Australia, for example, only three per cent of reported adverse reactions concern over-the-counter remedies, but another ninety-four per cent are for medicines prescribed by physicians. This may be because OTC remedies are self-administered, and so unwanted effects are seldom reported and, in any case, most consumers lack information on how to go about reporting, whereas professionals have clearly identified mechanisms for advising on adverse events for prescription drugs.
Although consumers in developed countries are supposed to be protected from fraud, quackery and unsafe products by their statutory authorities, unfortunately protection sometimes arrives after a catastrophe has happened, so being an informed and critical consumer is essential. In the next chapter we will examine the ways in which advertisers can influence how we self-diagnose and self-medicate. Astute advertising can make suckers out of any one of us. ‘Buyer beware’ is still a good maxim.
[i] National Institutes of Health Office of Dietary Supplements (2013). Multivitamin/mineral Supplements Fact Sheet for Health Professionals, P.1.
[ii] Freeman, L.W. (2001). Herbs as a medical intervention. In Freeman, L.W. and Lawlis, G.F., Mosby’s complementary & alternative medicine: a research-based approach. St Louis: Mosby. p.388.
[iii] Wachtel-Galor & Benzie, F.F. 2011 Herbal Medicine. http://www.ncbi.rim.nih.gov/books (accessed October 2015).
[iv] Lambert, C. (2015). Should you swallow it? New Scientist, 16 May, p.30.
[v] http://www.healthissuescentre.org.au/documents/items/2011 (accessed October 2015)
[vi] 6Eisenberg, D.M, Davis, R.B, Ettner, S.L., Appel, S., Wilkey, S., Van Romay, M. & Kessler, R.C. (1998) Trends in Alternative Medicine in the United States, 1990–1997: Results of a Follow-up National Survey. JAMA, 280: 1569–1575.
[vii] Jeffreys, D. (2004). Aspirin: The Story of a Wonder Drug. London: Bloomsbury Publishing, p. 13.
[viii] http://www.online-pharmacy.com [Accessed 22 March 2004]
[ix] Tang, S. (1996). Microbiological Quality of Herbal Teas. Therapeutic Goods Administration Laboratory Information Bulletin. Australia.
[x] Weatherall, M. (1990). In search of a cure. Oxford, New York: Oxford University Press. pp.v-vi.
[xi] The Age, (2003). Melbourne, Wednesday, 30 April, p. 1.
[xii] Consumerlab.com.Product Review: Echinacea. Wednesday, 2 July 2003. http://www.consumerlab.com
[xiii] Mazza, G. & Cottrell, T. (1999). Volatile Components of Roots, Stems, Leaves, and Flowers of Echinacea Species. Journal of Agricultural and Food Chemistry, 47(8): 3081–5.
[xiv] Perry, N.B., van Klink, J.W., Burgess, E.J. & Parmenter, G.A. (2000). Alkamide Levels in Echinacea Purpurea: Effects of Processing, Drying and Storage. Planta Medica, 66(1): 54–6.
[xv] Livesy, J., Awang, D.V., Arnason, J.T., Letchamo, W., Barrett, M. & Pennyroyal, G. (1999). Effects of Temperature on Stability of Marker Constants in Echinacea Purpura Root Formulations. Phytomedicine, 6(5): 347-9.
[xvi] Choice (2003). Echinacea—Power Pill or Placebo? November: 8–13.
[xvii] Nahin, R.L. and Strauss, S.E. (2001). Research into Complementary and Alternative Medicine: Problems and Potential. British Journal of Medicine, 322:161–4.
[xviii] Medicine Control Agency (2002). Report on the Safety of Herbal Medicines, p. 8.
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