Meetings and Conferences

World Congress of Pharmacy and Pharmaceutical Sciences

Pharmacists’ interactions with complementary and alternative medicine

A variety of aspects of the interaction between pharmacists and complementary and alternative medicines (CAMs) were discussed by the speakers at a joint symposium of the Academic Section, the Medicinal and Aromatic Plants Section and the Pharmacy Information Section of FIP on 5 September.

Dr Zhari Ismail, of the pharmacy faculty, University Science Malaysia, Penang, Malaysia, gave an overview of the regulatory standards applied to herbal medicines in the major countries of South East Asia. In some of these countries, notably Indonesia, herbal medicines have been officially recognised for some time, whereas in others, eg, Malaysia and Singapore, their legal status was still being formulated. Over 350 monographs for herbal medicines have been produced in Indonesia and standards for good manufacturing practice for all such products have been applied since 1991. In addition, pharmacists have to be involved in the production of herbal medicinal products. Quality control procedures in all the countries were more concerned with the detection of adulteration and impurities than with ensuring adequate levels of compounds necessary for activity, partly because, in many cases, much more work was needed to determine the chemical basis of activity. China and Japan had possibly the greatest amounts of documentation concerning herbal plants of almost any countries in the world, but its usefulness to scientific investigators was hampered both by language and unfamiliar terminology and concepts.

With regard to regulatory parameters, most of the countries concerned considered it mandatory to have procedures for authentication and identification, and also tests to establish that the preparations were free of toxic levels of scheduled poisons, steroids and added chemical substances. Although quantitative standards were less developed, it was noted that 100 of 187 preparations used in Malaysia were standardised in some way, implying some degree of quantification.

Dr Zhari stressed that little work had been done to test claims for efficacy but efforts were in progress to commence clinical trials. These would be of little use if standardised and characterised preparations were not used.

At present there were some considerable differences between the standards in the different countries but a harmonisation process had been under way since 1993 and monographs to define good quality material were being constructed, based on those published by the World Health Organization.

Efficacy

The issue of efficacy was considered further by Dr Brenda Waning (Massachusetts College of Pharmacy, United States) in her talk entitled, “What is the evidence for herbal medicines?”. Dr Waning mentioned that many articles asking the same question have been written in recent years, often with the implication that herbal medicine was not effective until proved otherwise by conventional scientific evidence based on clinical trials. Dr Waning discussed the various levels of evidence which had been proposed by Chase in 1998, the top one being randomly controlled, large scale, double blind clinical trials with the lower confidence limit of the result being greater than the proposed normal clinical benefit level. She outlined how problematic it was to apply such trials to complementary medicines because of difficulties in reconciling traditional diagnoses and concepts of disease with scientific methods and in ensuring consistency in the materials used. Individualistic prescribing and the fact that the medicine was often only part of the treatment were other factors which made for a much more complex scenario than with conventional, “orthodox” single chemical entity drugs.

Dr Waning also emphasised that evidence was not always lacking, but was often difficult to access. For example, in a recent study, it had been shown that only 71 out of 178 reported clinical trials in Chinese medical journals on stroke victims were available from the Medline database and over 80 Chinese medical journals were not abstracted by Western database compilers.

Dr Waning concluded by showing how evidence was, to some extent, a matter of perspective. She showed that the use of conventional medicines for a particular condition were often based on flimsy evidence, taking the use of acetazolamide for mountain sickness as a good example. Although widely recommended in travel medicine, it had only been tested on small groups of healthy males and its severe diuretic effects were not mentioned. She warned against the application of double standards and stressed that it was possibly time for a a paradigm shift in what was considered as evidence.

Dr Lana Dvorkin, also from the Massachusetts College of Pharmacy, outlined the various resources now available for information concerning complementary and alternative medicines. The dramatic increase in the use and sales of herbal products in the US was exemplified by the fact that the percentage of the general public taking them in a year had risen from 2.5 per cent in 1990 to 12.1 per cent in 1998. This had been accompanied by greater demands from the general public for information and Dr Dvorkin contended that pharmacists were the ideal persons who could provide the information required by the public. With this in mind, the Centre for Integrative Therapies in Pharmaceutical Care, dealing with substance-based alternative therapies, had been set up in Massachusets in 1999 with a website (www.mcp.edu/altmed) to enable pharmacists to glean such information. Although the world-wide web was useful for gaining information generally, the lack of referenced statements made it difficult to differentiate scientifically proven information from mere speculation. Well-known reference sources such as Martindale, Pubmed and Medlline were of some use but it was important to use the scientific names of plants and to search for topics as keywords rather than subject headings.

Adverse effects

Professor Peter Houghton (King’s College, London) discussed the adverse effects of herbal drugs. The pharmacist had to realise that “natural” did not always mean “safe”, but conversely several surveys had shown that a clear link between herbal medicines and toxic incidents only applied in less than 0.1 per cent of cases. Although the causes of adverse effects were many, the greatest problems, especially with herbal products obtained from the Far East, were because of misidentification, addition of toxic substances or synthetic drugs and, more generally, through interactions. Recent tragic incidents, where patients had developed severe kidney damage through the action of aristolochic acid, were cited as a good example of misidentification due to two Chinese crude drugs having a similar appearance and name to untrained people. Reports of synthetic steroids in “herbal” creams for dermatitis and eczema and of heavy metals in some patent medicines were not uncommon and had led to problems in patients using them. Professor Houghton said that the increasing concurrent use of herbal medicines with conventional medicine, often not disclosed to the doctor or pharmacist by the patient, was likely to result in an increase in adverse effects arising from interactions. Warfarin and ginkgo were likely to cause haemorrhage and the effect of St John’s wort on liver enzymes, causing a much-enhanced metabolic breakdown of cyclosporin and some anti-HIV drugs, had now become widely known. Pharmacists should make use of any surveillance schemes to alert regulatory authorities and others to possible instances of interactions and should also be able to alert patients to possible interactions when they wanted to use herbal drugs with some types of conventional medicines.

The need to incorporate teaching on complementary and alternative medicines in pharmacy undergraduate courses was being increasingly realised in the United States and in several other countries. Dr Gary Smith (University of Maryland, Baltimore, US) reported that over 70 per cent of the pharmacy schools in the US gave some teaching on the subject but that often the time devoted to it was rather short. He outlined the topics which students needed to learn and these comprised the product names, their active ingredients, uses (together with the level of evidence) and the various laws which applied to them. Students should also know about adverse reactions, bioavailability and information resources about the products. An interesting proposal made by Dr Smith was that students should spend time in a pharmacy selling complementary and alternative medicines and also communicate with patients using them. He stressed that the teaching on these products should be carried out in an interdisciplinary way in exactly the same way that it was taught for conventional medicines.

Consumer information

Eiichi Akaho (Faculty of Pharmaceutical Sciences, Kobe Gakuin University, Japan), in his talk on the quality of information given to consumers, noted that people in developed countries were increasingly taking responsibility for their own health rather than relying on health professionals. Studies in Japan had shown that 77 out of 200 patients with head and neck cancer were using alternative medicine for some aspect of their condition and 45 were using it directly to treat the cancer. Many believed that taking the products increased their quality of life. In view of this widespread use, it was important that guidelines to enable consumers to assess the value of information were made available. Important points that should be considered were credibility of authors, how accurate and up-to-date was the information, provision of references, warnings against possible toxicity and abilities to give feedback. In a survey of 184 websites concerning the herbal drug Opuntia, only 34 per cent referred to any scientific work carried out. Little information was available from any source on the effect of taking complementary and alternative medicines in pregnancy or when lactating.

In his conclusion, Dr Akaho outlined his proposals for “good complementary and alternative medicine practice”. Major points made were the need to buy from reliable sources, to follow directions as for ordinary drugs, to watch for interactions and not to take or use suspect products.