Medicines are critical in the diagnosis, prevention and treatment of diseases and will require disposal if they remain unused.  Disposal practices by consumers may result in dumping of unused and expired medicines into environmental media leading to some environmental impacts.  Community pharmacies are an important source of healthcare in general, and medicines in particular, for community members.  Community pharmacists play a key role in the consumption of medicines by community members.  The quality of the interactions during dispensing of medicines can contribute to promoting ecopharmacovigilance, the science and activities associated with the detection, evaluation, understanding and prevention of adverse effects in the environment. The aim of the study was to determine how the interactions between consumers and pharmacists could promote ecopharmacovigilance.

A survey was conducted in the Krowor Municipal Assembly area in Accra, Ghana, to assess the quality of interactions between pharmacists and consumers who sought pharmaceutical care from community pharmacies.  The results obtained were analysed to assess the potential of using the interactions to promote ecopharmacovigilance.

The survey showed that over 73% of community members surveyed reported first to community pharmacy for healthcare and a similar number (77%) got their medicines from the community pharmacy. Whereas all communications were in a language understood by the respondents, only 58% said there had been discussions with the pharmacist with respect to other medicines they may have.  More than 62% of respondents had not been told when to stop their medications.  Most respondents (98%) indicated that they add their unused medicines to their household trash for disposal.  Medication name, strength and dosage regimen were the most common features appearing on about 70% of labels with patient name not appearing on any labels. 

The interactions during dispensing are currently not sufficient to promote ecopharmacovigilance but can be utilised to create the necessary awareness on proper handling and disposal of unused medicines.

Keywords: Client-pharmacist interactions, community pharmacy practice in Ghana, environmental pollution, ecopharmacovigilance

The role of medicines in the diagnosis, prevention and treatment of diseases is important in maintaining the health of individual members of any society and the general society as a whole (Esseku & Esseku, 2014).  Medicines may be prescribed by, or used on the advice of, a healthcare provider.  Some persons may also use medicines because of past experiences with such medicines, whether their own or the experience of persons who may be known to them.  There are also those who take medicines prescribed for others or take medicines on the advice of persons who may not have any technical knowledge of the medicines (Esseku, 2015). In using these medicines, prescribers, dispensers, other health care providers and the users alike seek some particular effects which may be to give relief from some condition, shorten the duration of/or prevent the condition altogether (Ahorsu & Esseku, 2017). 

Medicines may, however, have some unintended effects when consumed. These unintended effects, when they negatively impact the health of consumers, are referred to as adverse effects (Leheny, 2017).  Pharmacovigilance (PV) is defined by the World Health Organization (WHO) as the science and activities relating to the detection, assessment, understanding and prevention of adverse effects or any other drug-related problem (World Health Organization, 2002). In recent years, an aspect of PV that has come to the fore is the concept of ecopharmacovigilance (EPV).  EPV has been said to describe the science and activities associated with the detection, evaluation, understanding and prevention of adverse effects on the environment (Holm, et al., 2013). Medhi and Sewal, however, have focused the definition of EPV on the effects on humans and other animals, defining EPV as “science and activities concerning detection, assessment, understanding and prevention of adverse effects and other problems related to the presence of pharmaceuticals in the environment, which affect human and animal species” (Medhi & Sewal, 2012).  The relevance of EPV (Velo, 2007) and how EPV affects the health and wellbeing of humans and the environment (Boxall, 2004) have been extensively discussed. 

Pharmaceuticals enter environmental media in varied ways (Esseku & Dodoo, 2013) (Ahorsu & Esseku, 2017). The manufacturing processes to produce agents containing active pharmaceutical ingredients (APIs) result in discharge of these products into the drainage system. These processes may also result in other forms of pharmaceutical waste such as cleaning chemicals, biologicals and unused/unusable packaging products, which will require disposal (Esseku, 2015). Following production, all the different participants in the pharmaceutical value chain will have some pharmaceuticals that need disposal. Consumers will also discharge waste products which will contain pharmaceutical products or their metabolites.  Figure 1 shows the ways pharmaceuticals enter the environment.

Figure 1: Entry of pharmaceuticals into some environmental media

Pharmaceuticals in the environment undergo various attenuation processes such as photo degradation, dilution, absorption by solids as well as aerobic and anaerobic breakdown (Sakrabani & Boxall, 2007) (Snyder, et al., 2010).  However, some pharmaceuticals and chemicals tend to persist in the environment in their original form or as metabolites. In addition, even after the various attenuation processes, pharmaceuticals present in the drainage system, although present in diluted concentrations, may be very relevant with respect to their effects on health.  This is because a range of impacts have been reported which are attributed to low-level exposure to pharmaceuticals (Boxall, 2004).  The effects of the presence of pharmaceuticals in environmental media are not clearly understood and may be complex as well as long-term on environmental flora and fauna. The possibility for inadvertent effects of pharmaceuticals to occur in the environment brings up a need for EPV wherever there is a potential for environmental media to be exposed to these products. 

At the time medicines are dispensed from suppliers, patients interact with the dispensers.  This interaction has been found to strongly influence the understanding of patients in relation to their health (Currie, et al., 2014).  In order to positively influence patients during these interactions, there is a need for effective communication between patients and the providers of pharmaceutical service.  Pharmacies are strategically placed in communities to provide opportunities to reduce the incidence of pharmaceuticals in the environment.  Take back schemes and events have been instituted in some jurisdictions (Daughton & Ruhoy, 2011).  Take back schemes allow community members to deposit their unused and expired medicines at any time.  On the other hand, take back events may be instituted at specific times and locations to receive unused and expired medicines from community members.  Environmental management plans have also been proposed for marketing authorization holders to develop and implement in order to control the impact of their pharmaceutical products on the environment (Holm, et al., 2013).  In Ghana, the Disposal of Unused and Expired Medicines Project (DUMP) established by the Pharmacy Department of Cocoa Clinic has been reported to receive significant quantities of unused and expired medicines (Ahorsu & Esseku, 2017).  This project is, however, limited to attendants of the Clinic and their associates. 

Dispensed medicines have labels which may be referred to when medicines are being used.  The labels of medicines are expected to have some minimum information comprising name of the patient, generic name of the drug, strength of the active ingredient, quantity of dispensed product, complete dose regimen in written and/or graphic form, name and address of the dispensing facility and dispenser, special instructions, date of dispensing and duration of use (Ministry of Health (GNDP), 2004).  The information on labels help in the rational use of medicines as consumers and their caregivers comply with the instructions provided on the labels.

There is a dearth of understanding on how pharmacies and dispensers of medicines can contribute to the reduction of the incidence of pharmaceuticals and their impact on the environment.  The main objective of this study was to ascertain the main facets of interaction between patients and dispensers of medicines as the patients from the community seek pharmaceutical care in the Krowor Municipal Assembly area (KroMA) and how these interactions may contribute to the promotion of ecopharmacovigilance. 

Survey Site

The site for the survey was community pharmacies in the Krowor Municipality. The pharmacies from which community members were surveyed are distributed throughout the assembly and are in all sections of the assembly: residential, commercial and industrial.

Krowor Municipality is in the Greater Accra Region.  It is located on the coast between the Tema West Municipality and Ledzokuku Municipality. The assembly covers a land area of 27.58km². (Krowor Municipal Assembly, 2021).  The main economic activities carried on by residents in the municipality are commerce (42.5% of residents), manufacturing (15.8% of residents) and agriculture (10.1% of residents). Approximately sixty percent (60%) of residents in the municipality are indigenes and forty percent (40%) settlers.  The indigenous language for the municipality is Ga.  However, being cosmopolitan, both indigenes and migrants communicate in Ga, Twi and English.

Population and sample size

The population of the Krowor Municipal Assembly area is estimated at 137,620.  This estimate was arrived at using projections of district populations from the Ghana Statistical Service (Ghana Statistical Service, 2019).  The calculation was done as set out in the supplementary material. The sample size for data collection was determined using the following formula:

Sample Size= [(z score)²   x  StdDev  x  (1-StdDev)]/(margin of error)²

The confidence level (z-score) of 95%, a margin of error of 5% and a standard deviation of 0.5 were used for this survey.  The calculation gave a figure of 384 as the ideal sample size.  A sample size of four hundred (400) was used for the study. To avoid bias, the participants were randomly contacted as they left community pharmacies from which they had accessed health service.  Every fifth client was contacted to participate in the study.  The questionnaire was administered from September to November of 2019.

Data Collection Techniques

Community members were contacted as they exited community pharmacies after receiving pharmaceutical service and the purpose of the study was explained to them.  Their consent, either written or verbal, was sought with respect to their participation in the study.  Once consent was obtained, a structured questionnaire was used to collect the relevant data. Participants had the option to complete the questionnaire themselves or for the questionnaire to be administered by a researcher. The questionnaire gathered information from the participants with respect to some demographics, their health-seeking behaviour and the primary sources of their medications.  Participants were also asked about their dispensing encounters with the dispensers and how they usually handle and dispose of their unused and expired medications. The dispensing encounters were assessed with respect to effectiveness in communicating.  The study sought information on the language used during the interactions, information on how the medications were to be taken and for how long, as well as what to do with unused and expired medicines.

Where participants had received dispensed medicines, their permission was sought and the relevant features on the labels of the dispensed medications were taken. The information on labels was compared to the required information for dispensed medicines as provided by the Ghana National Drug Programme (Ministry of Health (GNDP), 2004). The survey asked participants about medications they had from previous visits to the pharmacy, medications they kept for emergencies and medications they had for conditions they may still be treating. 

Data Analysis

Data from the surveys were entered into Microsoft Excel for analysis. Results for categorical and continuous variables were presented as numbers (percentages) and mean ± standard deviation (SD) respectively.

Respondents

Four hundred community members participated in the survey.  There were more male respondents (52%, n=207) than female (48%, n=193). The educational background of respondents cut across the spectrum from “no education” to “PhD”.  Figure 2 shows the distribution of the educational background of survey participants disaggregated by gender.

Figure 2: Educational background of survey respondents

Respondents ranged in age from sixteen (16) years to seventy-two (72) years of age.  Both modal and median age ranges of respondents was twenty-six (26) to thirty (30) years of age. This age range accounted for 23% of all respondents participating in the survey.    Figure 3 shows the age distribution of respondents.

Figure 3: Age distribution of respondents

Health Seeking Behaviour of Community Members

Most respondents (73.5%, n=295) indicated that their primary source of health care was the community pharmacy.  About a quarter of respondents (24.75%, n=99) indicated their primary source of health care as hospitals.  The trend was similar for males (73.9%; 24.2%) and females (73%; 25.4%).  Only 1.75% of respondents utilised over-the-counter medicine sellers (OTCMS) or herbal shops as their primary source of health care.  Figure 4 provides a pictorial representation.

Figure 4: Primary source of health care for community members in Krowor

All respondents who indicated the community pharmacy as their primary source of health care also identified the community pharmacy as their primary source of medicines.  However, a few (4%, n=16) of respondents who indicated that their primary source of health care was the hospital indicated they sourced their medicines primarily from community pharmacies, with the rest taking their medicines primarily from hospital and clinic pharmacies.

Interaction between Consumers and Healthcare Professionals

Language of Communication and Instructions on Medication Use

All participants in the survey (100%, n=400) indicated that the interactions they had with personnel in the community pharmacy were in a language they understood and that they had been given instructions on how to take their medications. 

Discussion regarding other medications

Forty-two percent (n=168) of respondents had been asked about other medications they may have as shown in Figure 5. Fifty-two percent (n=208) of consumers in Krowor do not get the benefit of having discussions on medications they may be on at the time of getting new medications.

Figure 5: Discussion on other medications clients may have

Duration of Regimen

Most respondents (62.5%, n=250) said they had not been told when to stop taking their medication.  Of those who had been told when to stop taking their medications, almost all respondents (93%, n=139) had been told to stop when the medications got finished and a few (5%, n=7) were told to stop when they had relief of symptoms.  In addition, some (13%, n=20) of these respondents indicated that they were also informed to stop taking the medications if they observed any adverse effects. 

When asked, most respondents (95%, n=380) indicated that they were not told how to deal with their unused medicines, with only a few (5%, n-19) saying that it had been discussed during dispensing of medicines.

Labelling of Dispensed Medications

The labels of dispensed medications showed that patient names and dates of dispensing were not usually captured.  Also, whereas some required information was provided on labels, none of the labels had all the required information.  Figure 6 shows the features of labels from Krowor that had various relevant information.

Figure 6: Features of labels on dispensed medications in Krowor

Handling of Medicines by Community Members

Medicines from previous visits

When asked whether they were able to complete all medications supplied when they seek health care, about eighty-one percent (n=168) of males and seventy-nine percent (n=152) of females responded in the affirmative.  When asked whether they had medications at home from previous visits, thirty-seven percent (n=76) of males and thirty-four percent (n=66) of females indicated that they did.

Medicines for Emergency and Other Use

Participants were questioned on medications they had at home for use in emergencies.  To this, 81% of males (n=168) and 83% of females (n=158) answered in the affirmative.  When questioned further on the types of medications they had at home, up to 84% (n=336) of all respondents indicated that they had medications which had been prescribed for pain at home.  Participants also identified other categories of medicines they had at home as set out in Figure 7 below.  Significant numbers of consumers reported having anti-malarial agents, antibiotics, medicines prescribed for pain and medicines for cold, cough and flu.  Although none of the respondents indicated that they had any medications for hormone replacement, 3% (n=12) of respondents (all female) indicated that they had oral contraceptives.

Figure 7: Medications consumers admit to having at home

Use of Medicines

Participants were asked when they will stop taking their medications. Sixty percent (n=240) of respondents indicated that they would take all their medications until it got finished and thirty-nine percent (n=165) stated that they would stop taking the medications when they got better.  Details are shown in Figure 8.

Figure 8: When consumers will stop taking their medications

Participants who indicated they had medicines from a previous visit to a healthcare facility were further asked about what they do with those medicines that were yet to be used.  The responses indicate that 70% (n=280) of respondents who had medicines at home kept them for use in the future, and 24% (n=96) passed their unused medicines on to family and friends.  Figure 9 shows the actions taken by consumers when they have leftover medicines.

Figure 9: What consumers do with their leftover medicines

Disposal of Unused and Expired Medicines

Respondents of the survey were asked about the means by which they dispose of medicines when the need arises.  Almost all (98%, n=392) of respondents indicated that they added solid and semi-solid medicines to the general waste for disposal (Figure 10).  With respect to liquid dosage forms, 81% (n=324) of respondents said they added them to the general waste, 4% (n=16) poured them down the drain, 8% (n=32) buried them and 5 % (n=20) used open burning when they disposing of these medicines.  None of the respondents returned their unused and expired medicines to the pharmacy or hospital for disposal. 

Figure 10: Methods of disposal used by community members for different dosage forms

Interactions with pharmacists

When community members seek health and need medications as part of their treatment, they require appropriate information in order to get the optimum from the medications (World Health Organization, 1985; 2012).  Their interactions with pharmacists at the time of getting their medications will provide the relevant information not only with respect to using the medications correctly but also with handling and disposing of unused medications appropriately.

The results of the study show that 73.5% of the respondents reported to the community pharmacy first when seeking healthcare as shown in Figure 4 and about 77% obtained their medications from community pharmacies.  This situates the community pharmacy as a critical point at which relevant information concerning medicines can easily be given to community members.  During the time of dispensing, community members in Krowor receive their information in a language they claimed to understand (100% of respondents) emphasising the ease with which such information can be sent to community members. 

The study, however, shows that this important resource is not always utilised effectively.  During their interactions with pharmacists, Figure 5 shows that only 42% of respondents had been asked about any medications they may have.  Thus, for 58% of respondents, any interactions that the dispensed medicines may have with medicines they already have were not identified and dealt with.  About 63% of respondents had not been told when to stop taking their medications, and only 13% of those who discussed when to stop taking their medications were told to stop taking the medications if they observed any side effects.  The incidence of side effects was, thus, not a major issue of discussion during the interaction between health care professionals and clients while seeking health care.  Without these relevant pieces of information, community members may stop taking their medications before they get the needed result.  Figure 8 shows that about 40% of respondents indicated that they would stop taking their medicines when they felt better.  Whereas this decision may be good when it comes to pain relievers, stopping antimicrobial medications too early may result in the development of resistance by the microorganisms.  Again, community members will also have medications which will subsequently have to be disposed of.

The results also showed that 95% of respondents were not told how to handle their unused medicines.  This lack of information resulted in community members taking their own decisions with respect to unused medicines: 70% would keep them for use in the future and 24% would pass them on to friends and family who they assessed to need them.  Only 4% said they would treat unused medicines as if expired.  This brings to the fore a knowledge gap and shows a need to communicate information such as how to dispose of unused and expired medicines to community members during interactions on their medicines. 

The labels of medications that had been dispensed also showed a lack or low incidence of some relevant information.  None of the labels given to the respondents had the names of the consumers indicated on them.  This could result in medicines being consumed by the wrong persons resulting in adverse drug reactions.  As shown in Figure 6, just about fifty percent (50%) of the labels viewed showed the duration of use of the medications.  These labels, thus, fall below the expected standards for labels of medicines.  The lack of critical information could lead to non-use or wrong use of the medicines.  When consumers are unsure of the medications, they may not use them resulting in an increase in the quantities that have to be disposed of.  Where consumers use the medicines wrongly, they could result in the incidence of adverse effects.

Implications for EPV

The medicines that community members are dispensed with during the periods in which they seek healthcare may remain unused or may expire while in their custody.  Consumers may also have no use of medicines they acquired for future use or for emergency situations.  Where the use of medicines results in the incidence of side effects, consumers are likely to stop taking the medications and these will remain unused.  These medicines will have to be disposed of. 

In this study, up to 83% of respondents had medicines which they said they had for use in emergencies.  Consumers also had a variety of medicines in their homes as shown in Figure 7.  Although these were supposedly for use during emergencies, the medicines that were identified included antimalarial agents, antibiotics, analgesics and anti-inflammatory agents.  The categories of medicines community members have in their homes are comparable with the categories of medicines that are largely used in the Ghanaian society (Ministry of Health, 2007).    Thus, the study shows that community members will tend to have in store medicines they use often for the management of various health conditions.  When medicines are stored for use, there will be a need to dispose of them when they expire.  In order to protect the environment, there is the need to inform community members on how to handle their unused medicines.

Nearly all community members surveyed (98%, n=392) added their solid and semi-solid preparations to the general waste for disposal while about eighty-one percent (n=324) do the same in respect of their liquid preparations which are to be disposed of, Figure 10.  This method of disposal results in most medicines ending up in dump sites which will result in contamination of surrounding soils (Shield, 2011) and water sources (Davis, et al., 2006).  These figures, however, are at variance with the findings made by Atinafu et al (2014).  They found that only about sixteen percent (16.4%) of respondents disposed of their unused medicines by putting them in the trash. 

In a previous work, Esseku (2015) suggests that community members contribute up to fifty-five percent (55%) of medicines that are disposed of.  This means that consumers are critical if the environmental impact of medicines is to be reduced.  Consumers must be engaged on all fronts to ensure that there is comprehensive understanding of the use and disposal of medicines.  Consumers also have an important role to play in becoming advocates for the proper use and disposal of medicines.

The engagement of consumers could involve the introduction of take back schemes (Ahorsu & Esseku, 2017).  These schemes encourage the regulated disposal of medicines.  The schemes will also result in reduced environmental impacts as the sites of disposal may be marked to control contamination of other areas in the future.  The study shows that community members do not return their unused and expired medicines to the pharmacy or hospital.  These centres are areas where unused and expired medicines can be mobilised to reduce indiscriminate disposal.  As has been reported by Ahorsu & Esseku (2017), the use of such centres can result in the mobilisation and controlled disposal of significantly large quantities of unused and expired medicines.

The interactions community members have with pharmacists when receiving healthcare and medications provide a significant opportunity to get community members to understand why it is important to dispose of unused and expired medicines properly and how to do so.  This would result in the effective engagement of a significant stakeholder group in ecopharmacovigilance.  As a healthcare delivery point where communication is effective, the community pharmacy is critical for providing relevant information on the handling and safe disposal of unused and expired medicines.    The study, however, showed that this resource is not effectively utilised for ecopharmacovigilance, as discussions on handling and disposal of unused and expired medicines are not usually part of engagements during the dispensing of medicines.  The engagements with community members when dispensing medications should be utilised by pharmacists to educate them on how unused and expired medicines should be handled.

The labels of dispensed medicines provide a good opportunity for relevant information to be provided to minimise the quantities of medicines that need to be disposed of and thereby contribute to ecopharmacovigilance.  From the study, it is clear that not all the relevant features of labels are captured on dispensed medicines.  Providing all the relevant information on all dispensed medicines will promote the rational use of medicines and reduce the quantities of medicines that remain unused or expire in the custody of consumers. 

Providing all the relevant information to community members through discussions and labels will empower them to use their medicines properly.  In addition, community members could become advocates in their communities as they are empowered with knowledge and understanding on the proper handling of unused and expired medicines. 

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