Discussion

This is the first study to explore herbal-product users’ experiences of adverse effects following herbal-product use, and their likely behaviour if such problems occur. It was found that around 4% of respondents said they had experienced adverse effects that they attributed to their use of herbal products. Some herbal-product users would act differently if they experienced adverse effects, depending on whether the product involved was a conventional OTC medicine or a herbal product. The data also suggest potential underutilisation of the pharmacist for advice on adverse effects associated with either type of product.

The first objective of the study was to determine what types of herbal products are purchased by consumers in pharmacies and health-food stores, and herbal-product users’ use of other O TC medicines, whether conventional or complementary. Overall, consumers named garlic products, herbal sedative/hypnotic preparations and evening primrose oil/starflower oil as the products they purchased most frequently. These findings may more accurately reflect what are the most popular herbal products among consumers than do some market survey data on retail sales of complementary medicines, which have excluded ‘food supplements’, including garlic products.^^

In addition to herbal products, most consumers also use conventional OTC medicines. This also reflects others’ findings that CAM is used mainly in addition to, and not instead of, conventional medicine.^^ Also, most herbal-product users (78%) use vitamins/minerals and/or food supplements, and around a half (49%) use ‘natural’ health products other than herbal products, such as homoeopathic medicines. This reflects others’ findings that CAM

users do not restrict themselves to one complementary therapy, but utilise a range of CAM approaches/^^^^^

One of the key objectives of this study was to determine who herbal-product users would consult for advice in choosing herbal products and, in particular, whether users seek advice from a pharmacist. The issue of whether individuals wishing to use CAM first seek advice or information from an appropriate source was first raised in section 1.5. Data from this study have indicated that only a small proportion of herbal-product users seek informed and/or professional advice when selecting herbal products — overall, only

6% of users choose herbal products solely on the basis of a doctor’s, pharmacist’s or

herbalist’s recommendation. By contrast, 83% choose herbal products on the basis of information or advice from other sources (for example, their own knowledge or friends’/relatives’ recommendations) which are unlikely to provide informed and/or professional advice. Only 11 % use both approaches to obtaining information. A related finding was that some herbal-product users obtain herbal products from supermarkets, grocery stores and ‘other’ outlets, possibly via the internet, where informed advice is unlikely to be available.

Two other studies have been published since this study was completed which confirm the present findings that only a small proportion of complementary-medicine users seek advice on products from a pharmacist, and that the majority of users rely on their own knowledge or recommendations from f r i e n d s / r e l a t i v e s . A survey of purchasers of homoeopathic remedies from pharmacies found that only 5% were influenced by pharmacy staff in their purchase and only 14% had sought advice from the pharmacist on what specific remedy to use; more had used their own knowledge to inform their

decision or had sought advice from a doctor (29% for each).'°® Bennett and Brown reported similar findings from their survey of herbal-medicine use among patients enrolled in a health maintenance organisation in the US.'°’ The majority (51.4%) of their respondents chose to use herbal medicines as a result of a friend's or relative’s recommendation, and 22.9% chose them only on the basis of reading and media advertisements.Sources of information considered most useful were the popular media (39.0% of respondents), and friends/relatives (34.1%). Bennett and Brown also reported that the majority of herbal-product users in their survey bought products from health- food stores and mass merchandiser/grocery stores (31.1% for each); less than 9% of respondents purchased herbal products from pharmacies.'®’

The lack of informed and/or professional input into herbal-product choice may have implications for the safe, effective and appropriate use of such preparations. For example, users may select products that are not appropriate for them or their condition, or they may self-treat with herbal products of unproven efficacy instead of seeking proven treatment. A related finding is that although a large proportion of respondents in this study purchase their products from pharmacies and health-food stores (this is to be expected since these were the 2 settings for the study interviews), some users also purchase herbal products from other retail outlets, such as supermarkets and grocery stores, via mail order, and from other sources, possibly the internet, where informed and/or professional advice is unlikely to be available. These findings have particular importance for pharmacists, as although a large proportion of users obtain herbal products from a pharmacy (again, this is to be expected as BTC pharmacies were one of the settings for the study), only 6% of users include the pharmacist among sources of information and advice on herbal products.

Users’ preferred sources of advice raise concerns as users relying on non-professional sources may receive poor advice and be misinformed about the efficacy and safety of complementary medicines. Vickers ef a/have shown that staff in health-food stores readily suggest complementary medicines and/or give health-care advice that may be in ap propriate.In their study, a researcher visited 29 health-food stores in London, none of which employed a pharmacist. According to a defined protocol, the researcher approached a member of staff and claimed to be suffering from symptoms associated with serious pathology (severe daily headaches of recent onset). Staff in 27 of the 29 shops offered some form of specific therapeutic recommendation, for example, a specific therapy, product or behaviour. Only 7 staff members suggested consulting a GP, and only one took the most ‘correct’ course of action which was to ask further questions and then immediately recommend a consultation with a GP."° A similar study involving a researcher who visited 40 health-food stores in Hawaii, US, while posing as the daughter of a patient with breast cancer also found that health-food store staff readily provided information and product recommendations."'

Other researchers have compared the level of advice given by pharmacy and non­ pharmacy outlets (discounters, superstores, corner shops and garages) to purchasers of general sales list medicines."^ Although this study showed that many pharmacies (60%) did not give advice or ask questions of purchasers of conventional O TC medicines, staff in non-pharmacy outlets did not give a/?/advice or ask a/?/questions. It is not known if this lack of intervention also occurs with purchasers of complementary medicines in non­ pharmacy outlets, or, as in Vickers ef a/s study, if questions were asked and advice given, whether this would be appropriate and correct. It is also not known whether purchasers of complementary medicines in pharmacies receive advice or are asked

questions. Nevertheless, a//pharmacies are required to maintain certain standards in the sale of pharmacy medicines, and to ensure that advice is available for all prospective purchasers of general sales list medicines and vitamin and mineral supplements."^ Some complementary medicines are pharmacy medicines or general sales list medicines and, therefore, the same standards apply to those products.

Pharmacists also have a professional responsibility to ensure that any products they sell or supply are of suitable quality and are generally considered ‘safe’."^ This should give the consumer in a pharmacy some protection against complementary medicines that are not fit for medicinal use. Other retail outlets have a financial interest at least in selling products that are of suitable quality, but do not have the professional responsibility in this regard that applies to pharmacists.

An issue related to users’ sources of advice on complementary medicines is that many individuals do not disclose complementary-medicine use to their doctor or pharmacist. Bennett and Brown found that 86% and 96% of herbal-medicine users did not discuss this with their doctor or pharmacist, respectively.'®’ Users’ disclosure of complementary medicine use to GPs may partly be influenced by who recommended the remedy to them and where they obtained it, and their perceptions of their GPs’ beliefs about such products."^ This may account for the finding reported in chapter 2 that few herbal- medicine users would consult their GP and/or pharmacist if they experienced an adverse effect associated with the use of a herbal product. There is evidence to support the suggestion that non-disclosure can lead to problems. For example, there are reports of important interactions between St John’s wort and certain prescribed medicines in patients who began self-treatment with St John’s wort without first discussing this with

their doctor.®^

Since data were not collected from respondents on why they would not consult a pharmacist (or other health-care professional, for example, a GP), it is possible only to speculate on the reasons for this. Possible explanations are that users or potential users of herbal products do not want to disclose herbal-product use to a pharmacist, or they may believe that pharmacists are not knowledgeable about such products. Alternatively, they may perceive that it is difficult or inconvenient (either for the consumer or the pharmacist) to consult the pharmacist about such products, or they may not view the pharmacist as a source of advice on medicines in general, or there may be other reasons. Nevertheless, even if only a small proportion of users seek pharmacists’ advice on herbal products or other complementary medicines, the argument is that pharmacists should have sufficient evidence-based knowledge to be able to advise users appropriately. However, at present, little is known about the level of training that practising pharmacists have received or undertaken in areas of CAM. This is addressed in the study described in chapter 3.

Others have investigated consumer perceptions and attitudes towards the advice-giving role of the pharmacist."^ In a survey of 261 members of the public, Margie era/found that just over half of respondents (55.6%) said they felt at ease about asking the pharmacist for advice, whereas the remainder felt awkward about asking the pharmacist for advice, or felt more at ease asking other members of pharmacy s t a f f . I n a survey of consumers in 4 pharmacies in Canada, Taylor found that 145 of the 151 respondents had not wanted advice from the pharmacist on non-prescription medicines, mainly because they had used the product before or had received advice elsewhere (for example, from

their doctor)."^ It is not known if these reasons apply to why herbal product users do not seek advice from pharmacists.

Section 1.4. of the introduction to this thesis summarised evidence that CAM users are not a homogeneous group, but that they vary in terms of their views on satisfaction with GPs, healthy life-style, confidence in prescribed drugs, faith in medical science, harmful effects of medical science and scientific methodology.^' The view that users are not a homogeneous group supports our findings of differences between BTC and H&B respondents. For example, H&B respondents were more likely than BTC respondents to choose herbal products recommended by a CAM practitioner other than a herbalist, and were also more likely to use herbal products falling into the ‘other products’ category. There may be several explanations for these findings. These differences may reflect a more ‘adventurous’ approach towards choosing herbal products among H&B respondents than BTC respondents, or that a wider range of herbal products is available in H&B stores than in BTC stores. Alternatively, these results may have arisen from repeated testing, although this may be unlikely as p < 0.001 was used to indicate statistical significance.

Several of the study’s key findings relate to herbal-product users’ behaviour with regard to reporting adverse effects associated with herbal products and conventional OTC medicines. In particular, herbal-product users said they would be less likely to consult their GP for adverse effects (‘serious’ or ‘minor’) associated with herbal products than for adverse effects associated with conventional OTC medicines. There may be several reasons for this finding. Herbal products are largely used on a self-treatment basis and some users may not realise that they can consult their GP about adverse effects associated with such products. Others may be reluctant to admit herbal-product use to

their GP by consulting him/her for adverse effects, while some users may feel it is more appropriate to consult a herbal practitioner, particularly if the herbal remedy was obtained from this source.

The study findings raise concerns not only with regard to reporting of adverse effects associated with herbal products, but also for those associated with conventional O TC medicines. For a ‘serious’ adverse effect, only 290 respondents (56.3%) would consult their GP; for ‘minor’ adverse effects associated with conventional OTC medicines, only 108 respondents (2 1.0%) would do so. Similarly, less than 10% would consult a pharmacist following a ‘serious’ or ‘minor’ adverse effect associated with a conventional OTC medicine. Overall, the study appears to have uncovered potential underutilisation of the pharmacist for advice on adverse effects — less than 12% of herbal-product users interviewed in this study said they would consult a pharmacist if they experienced an adverse effect associated with either a herbal product or a conventional OTC medicine. Although at the time of the study pharmacists were not included in the CSMs’/M CA’s yellow card scheme for ADR reporting, pharmacists are a source of information on ADRs associated with both prescription and OTC products and are in a position to advise patients/consumers to consult a GP, or to do so on the patient’s behalf, with regard to a suspected ADR.

The yellow card scheme for ADR reporting relies not only on patients detecting and reporting adverse effects to their GP or pharmacist, but also on GPs passing onto the CSM/MCA those reports that meet ADR reporting criteria (at the time of this study, the yellow card scheme allowed submission of reports only by doctors, dentists and coroners; pharmacists were not included in the scheme, but could be involved in the process, for

example, by informing a patient’s GP of a suspected ADR on the patient’s behalf). Deficiencies in any of these steps will lead to under-reporting.^^ Even those suspected ADRs which are reported to a GP and which meet ADR-reporting criteria may not be reported on to national pharmacovigilance centres. In the UK, hospital physicians have been shown to grossly under-report ADRs that meet CSM criteria;' there is no evidence to suggest that GPs are any more diligent.

Furthermore, deficiencies in the reporting process may be even more likely to occur with herbal products.^^ The yellow card scheme has always included licensed herbal products and, in October 1996, the scheme was extended to include unlicensed herbal products."® However, reporting for herbal products by doctors is still limited."’ In April 1997, the CSM extended the yellow card scheme to include all hospital pharmacists and community pharmacists in the 4 CSM regions as part of a pilot scheme;"’ community pharmacists were seen as having a critical role in areas of limited reporting by doctors, namely, OTC medicines, and licensed and unlicensed herbal products."’ An analysis of reports submitted during the pilot scheme showed that, although numbers of reports were low, community pharmacists submitted a greater proportion of reports relating to herbal products than did GPs.'®^ Following the pilot study, the scheme was extended to include all community pharmacists.'®' This development reflects the increasing awareness of the need to monitor the safety of herbal products, and supports our findings that users of herbal products experience adverse effects that they attribute to use of these products. The CSMs’ recognition of the pharmacist’s role in ADR reporting for licensed and unlicensed herbal products also supports our finding that some users of herbal products say they would consult a pharmacist if they experience adverse effects following herbal- product use.

The findings described above with regard to users' behaviour if they experienced adverse effects associated with herbal products reflect users’ responses to a question describing a hypothetical situation. However, data are also available from the 4% (n = 21) of herbal- product users in this study who said they had experienced adverse effects associated with herbal products. Most of these respondents rated the adverse effect as ‘moderate’ or ‘mild’, and stopped taking the suspected product. Only 3 cases were rated (by users) as ‘severe’, and only 3 (including one ‘severe’ report) said they had reported the adverse effect to their doctor, although it was not possible to confirm this. These data suggest that adverse effects associated with herbal products experienced by users in this study are generally not perceived (by users) to be of serious concern. However, as numbers involved are small, these data should be interpreted cautiously.

In addition to the usual limitations with survey data, such as problems with recall, this study has several other limitations which may have implications for the reliability of the findings. Several limitations relate to our sample. For example, our sample comprised a large proportion of females. Data were not collected on people who refused to take part in the survey, therefore it is not known if the female bias resulted from interviewers approaching more females than males, from females being more willing to participate in the survey than males, that a greater proportion of females was present in the stores at the time of the survey, or that more females than males use herbal products. Other studies have found that a greater proportion of CAM users are female, although do not report figures as high as reported here. Also, the majority of respondents were of Caucasian origin, so the results cannot be generalised to other users of herbal products in the UK. Another limitation relating to our sample, is that it cannot be stated definitively that users interviewed in BTC stores were not also interviewed in H&B stores. It was not

possible to check this as respondents were not asked to provide their name and/or address. However, it is unlikely that this would have occurred, especially where the BTC store used was Cardiff and the H&B store in Swansea.