STRENGTHS AND LIMITATIONS OF THIS STUDY

Inclusion of adequate number of study participants increases generalisability of the findings to similar settings.

Factors related to disposal practices, knowledge and attitude were not identified.

The pharmacological or therapeutic class of unused medicines was not determined.

The data collected at single time point may not account for variation of outcomes overtime.

As the study setting is a hospital, the findings may not represent the general community.

Introduction

The use of medicines is increasing globally and was expected to reach over 4.5 trillion doses in 2020, a 24% increase from 2015.1 However, patients may not consume all prescribed and over-the-counter medicines, leaving large amounts of unused or expired medicines at home.2 3 The magnitude of unused medicines varies across countries, ranging from 41.4% to 98% from which the least was from Ethiopia and the highest from Ghana.4–9 Adverse drug effects, prescribing practices, dispensing practices, lack of awareness of potential harm, poor attitude towards disposal of unused medicines, improvement from illness, patient non-adherence and keeping for future use are among several factors that can contribute to the accumulation of unused medicines at home.2 5 10 11

Safe disposal of unused medicines, particularly by consumers, is a global concern. The recommended disposal methods for unused medicines by different authorities or guidelines are return to donor/manufacturer, landfill, incineration and sewer.12–14 The US Food and Drug Administration (FDA) recommends community ‘take-back programmes’ as the best option for safe disposal of unused medicines at household level. If there is no such option, consumers should read the labelling for disposal instructions and dispose accordingly. The FDA also recommends that if there are no disposal instructions, mix unused medicines with undesirable substances and place them in sealable garbage. Unused medicines should not be flushed into toilet/sink, unless specifically specified.13 Moreover, a study conducted in developed countries identified various activities undertaken by pharmacists to reduce medicine waste, including proper storage management, prescribing practices, dispensing and the collection of unused medicines from patients.15 In this study, pharmacists considered activities related to managing leftover medicines to be less feasible.15 Other studies also in the Netherlands have showed that a substantial proportion of patients are willing to use unused medicines returned by other patients as far as quality is guaranteed,16 and medicines dispensed for longer periods were more likely to be unnecessarily wasted.17 Gaps related to activities undertaken to reduce medicine waste are expected to be more due to limited budget and healthcare infrastructures.

Despite available recommendations, improper disposal of unused medicines is a worldwide problem because of the lack of effective collaboration among pharmaceutical factories, government officials, healthcare providers and patients; limited budget allocation to support medicine disposal and limited community awareness of recommended disposal methods.18–20 In particular, limited budgets, poor design of drinking water sources, ineffective take-back programmes and limited community awareness worsen the problem in developing countries.4 12 19 21 22

Improper disposal of unused medicines causes problems such as toxicity to humans, antimicrobial resistance, wildlife poisoning and ecosystem contamination.3 21 23

In Ethiopia, there are medicine disposal waste management directives that include a drug take-back programme.14 However, there has been limited effort to increase public awareness of the safe disposal of unused medicines and allocated budgets to support unused medicine disposal.

There were no data regarding disposal practices, knowledge and attitude towards unused medicines among patients visiting the study hospital. Therefore, this study aimed to determine disposal practices, knowledge and attitude towards unused medicines among patients visiting the Debre Tabor Comprehensive Specialized Hospital.

MethodsStudy design, setting and period

The descriptive cross-sectional study design was conducted through face-to-face interviews using structured questionnaires containing both open- and closed-ended questions at the Debre Tabor Comprehensive Specialized Hospital. This hospital is the only specialised hospital in the South Gondar Zone of the region and is specifically found in Debre Tabor Town, the capital city of the South Gondar Zone. The Debre Tabor is 97 km from Bahir Dar, the capital city of the Amhara National Regional State, and 667 km from Addis Ababa, Ethiopia’s capital city. The hospital has four pharmacy units: outpatient, inpatient, antiretroviral therapy pharmacy and emergency. This study was conducted at an outpatient pharmacy (OPD) from 31 May to 30 June 2022.

Participants and inclusion criteria

The source population included all patients who visited the hospital to receive a prescription.

The study population included patients who visited the OPD unit during the study period. OPD was selected because most of the oral medications dispensed to patients for home use were from there. All patients 18 years of age and above, attending the OPD dispensary unit from 31 May to 30 June 2022 and willing to participate were included in the study. Patients with cognitive and/or communication problems were excluded from this study.

Sample size calculation and sampling techniques

The sample size for the study was determined using a single population proportion formula with the following assumptions: 50% of the population had unused medicines at home, with a 95% CI and a 5% margin of error to estimate the total sample size. Based on these assumptions, the required sample size was 384. Since fewer than 10 000 in total came to the OPD during the study period (average of three consecutive months (n=600)), a sample reduction formula was used to calculate the desired sample size, which was 234. After adding a 10% non-response rate, the final sample size was 260. Systematic random sampling of patients waiting for prescriptions was used following the determination of two sampling intervals and selection of the first study participant by lottery method.

Study variablesDependent variablesDisposal practice

Disposal practices were assessed using five items.4 5 13 14 The first and the second items have a response option of yes or no, whereas the second, third, fourth and fifth items have outlined possible answers with an instruction of ‘select all that apply’. In addition, in the second item, if the participants had a response in addition to or other than the given outlined possible responses, they were invited. Responses of yes and no were given a code of 1 and 0, respectively. Responses were categorised into appropriate and inappropriate with a code of 1 for the former category and zero for the later.

Knowledge

The knowledge-related questionnaire contains eight items4 5 13 14 of which four were with yes or no response options, while the others included the given outlined possible responses with an instruction of ‘select all that apply’. Participants were also invited to add responses if they had additional or other responses. Yes response was coded as 1 and no coded as 0. Responses were classified as correct and incorrect, with given a code of 1 and 0, respectively.

Attitude

Six-item questions were used to assess attitude of participants towards unused medicines.4 5 13 14 The response options had a five-Likert scale, that is, strongly disagree, disagree, neutral, agree and strongly agree. Codes 1 to 5 were given for the scale in the respective order.

Independent variables include sex, age, marital status, educational status, residency and occupation.

Outcome measurement

Each response of study participants to each disposal practice–related questions were described in frequency and percentage. Each response was weighted against the local guideline14 and the US FDA recommendations,13 and one which aligned was considered appropriated disposal practices.

Moreover, each response of participants to knowledge-related questions was described in frequency and percentage. Responses that were in line with scientific facts and existing recommendations13 14 were taken as correct. In the Likert scale, questions used to assess attitude, each response was narrated and a response of either agree or strongly agree was considered towards favourable attitude.

Prevalence of unused medicines was assessed using a question: ‘Do you or anyone in your household have medicines that are no longer needed?’

Data collection procedures and data quality control

Face-to-face interviews were conducted using a structured questionnaire to collect data (online supplemental file 1). The questionnaire was prepared in English, translated into the local language, Amharic, and then, back-translated into English by experts to maintain consistency. The data collection tool was pretested on the study population by taking 5% of the sample size before commencement of the actual data collection. The data collectors were trained, and the data collection process was supervised daily. The data were checked daily for completeness and consistency.

Operational definitions

Unused medicines refer to expired drugs or leftover drugs of prescription and over-the-counter medicines.

Knowledge refers to clients’ correct answer to knowledge-related questions.

Attitude refers to the clients’ appropriate answer to attitude-related questions.

Practice refers to clients’ correct answer to unused medicines’ disposal practice–related questions.13

Data analysis

Data were checked and cleaned for completeness and consistency and then entered into SPSS V.26.0 and analysed. All variables of interest related to disposal practices, knowledge and attitude towards unused medicine were assessed descriptively, and the results were presented in the form of statements, per cent and tables.

Ethical consideration

Ethical approval was obtained from the Institutional Research and Ethical Review Committee, College of Health Sciences, Debre Tabor University (ref: CHS/DTU1484/2022). Informed consent was obtained from all respondents before beginning the study. Patient identifiers were anonymised to maintain confidentiality. The study was conducted based on the Declaration of Helsinki.

Patient and public involvement

Patients and the general public were not involved in the planning, execution, reporting or distribution of this study. Once their informed verbal consent was obtained, the adult customers who were routinely sampled were involved as participants for the data collection period.

ResultsSociodemographic characteristics of the respondents

From 260 individuals who were requested to participate in the study, 257 agreed and included in the study, with a non-response rate of less than 2%. Of these, approximately 55% were male. Concerning residence, 54.1% of participants lived in urban areas; regarding educational status, 37% had college-level qualifications and above (table 1).

Table 1

Sociodemographic characteristics of participants in Debre Tabor Comprehensive Specialized Hospital, Debre Tabor, Ethiopia, June 2022 (n=257)

Knowledge of unused medicine disposal

Approximately 50% and 73% of respondents did not know about medicine waste and did not receive any prior information about medicine disposal instructions, respectively. However, 71% of participants knew that the inappropriate disposal of unused medicines could cause harm. Almost 39.7%, 17.9% and 42% of respondents responded that inappropriate disposal of medicines can contaminate the environment, kill wildlife and cause accidental swallowing in children, respectively. Moreover, 55% of participants suggested that providing proper guidance to consumers could reduce the hazardous effects of unused medicines (table 2).

Table 2

Respondents’ knowledge of unused medicines disposal in Debre Tabor Comprehensive Specialized Hospital, Debre Tabor, Ethiopia, June 2022 (n=257)

Attitude to unused medicine disposal

The majority of respondents (79%) agreed about the potential risks related to the presence of unused medicines at home, and 63.4% strongly agreed that children are more vulnerable to the risks associated with unused medicines in the household (table 3).

Table 3

Respondents attitude towards unused medicines disposal in Debre Tabor Comprehensive Specialized Hospital, Debre Tabor, Ethiopia, June 2022 (n=257)

Disposal practice of unused medicines

Almost 47% of respondents had unused medicines at home. The most common disposal method for unused medicines was throwing in the household garbage (42%), followed by flushing them down the toilets/sinks (30%) (table 4).

Table 4

Respondents unused medicines disposal practice in Debre Tabor Comprehensive Specialized Hospital, Debre Tabor, Ethiopia, June 2022 (n=257)

Discussion

The consumption of medicines has increased over time,1 which may contribute to high accumulation of unused medicines at home.3 In the present study area, approximately 47% of 257 respondents reported that they had medicines in their homes at the time of data collection. This finding is lower than those reported in studies conducted in Ghana (98%),9 Harar (66.2%),6 Afghanistan (95.3%),24 Australia (60%),7 Indonesia (95.6%),11 Tanzania (70.2%)8 and Gondar (55.9%).5 In contrast, the finding in this study was higher than that of a study conducted in Mekelle, Ethiopia (41.4%).4 This disparity in findings might be due to differences in study settings (general community vs patients visiting healthcare facilities, hospitals vs health centres), presence/severity of morbidity, perceptions and awareness of the participants regarding medicines.

The reasons given by the respondents explaining why they had unused medicines at home were improvement of illness (53, 43.5%), change of prescription by the doctor (40, 37.8%), intolerable side effects (37, 30.3%) and keeping for future use (12, 9.8%). These results differ from those of the studies conducted in Indonesia2 11 and Ethiopia.4 5 These discrepancies among findings may be related to study settings and sociodemographic characteristics of participants. For example, studies in Indonesia included participants from the general community while ours from individuals who visited OPD services. Moreover, studies from other parts of Ethiopia, in Tigray, included more proportion of urban dwellers and Amhara region participants who attended health centres unlike ours.

Regarding common disposal practices for unused medicines, the present study showed that throwing them in the household garbage was the most commonly practiced disposal method. This is in line with studies in Ethiopia4–6 but in contrast to studies in Ghana and Afghanistan9 24 which found that burying unused medicines in the ground and keeping them at home until they expired were the most common disposal practices, respectively. Keeping unused medicines at home until expiration was the most common disposal method used in Indonesia.2 11 Returns to pharmacy were almost the least practiced disposal method revealed by previous studies in different countries.4–6 9 These findings were consistent with those of the present study.

Differences in findings may be attributable to disparities in awareness, attitude, morbidity and efforts of local healthcare providers and health offices to promote the safe disposal of unused medicines.

According to the current study, 48.6%, 48.8%, 70%, 26.8% and 71.2% of respondents reported knowing about medicine waste, mentioned expired medicines as medicine waste, checked the expiry date of medicines, received instructions on how to dispose medicines waste and agreed that inappropriate disposal could cause harm, respectively. Most participants believed that providing guidance to consumers regarding disposal of medicines waste would minimise or control the harm caused by their inappropriate disposal. Moreover, in our study, participants responded that pharmacists were primarily responsible for raising consumer awareness. These findings are not in line with those discovered in Harar,6 Mekelle,4 Gondar5 and Indonesia.11 Studies in Harar6 and Mekelle4 mentioned electronic media and physicians as the major methods to raise consumer awareness, respectively. Moreover, in a study by Mekelle, more participants responded that providing guidance to consumers helps minimise harm related to the inappropriate disposal of unused medicines compared with the present study.4

Concerning the attitudes of participants towards the disposal of unused medicines, 63.4%, 24.1%, 16.3% and 8.2% of participants in our study strongly agreed that children are vulnerable to harm from improper disposal of unused medicines, that lack of information on safe disposal of medicines waste and presence of unused medicines at home pose health risks and that healthcare provider advice about safe disposal of medicines waste is necessary, respectively. Furthermore, 28% and 29.6% of respondents strongly agreed about the value of a mandatory take-back programme and the initiation of outreach activities to raise consumer awareness, respectively. In this regard, previous studies have reported on the proportion of respondents who strongly agreed that children can potentially be harmed, take-back programmes are valuable, help from health professionals is needed and awareness programmes should be initiated. However, the magnitude of these proportions might vary according to differences in study setting, level of morbidity of participants and previous experience of disposal of unused medicines.2 4 6 25

The findings of the present study indicate the need to implement an awareness creation campaign through appropriate media to promote proper medicine waste disposal practices. There is also a need for government officials to allocate budgets to facilitate the safe disposal of unused medicines.

Strengths and limitations of the study

The strength of this study is that it is the first in this area to describe how unused medicines are disposed of among patients visiting an OPD unit. However, a limitation of this study is that it was descriptive and cross-sectional, that is, it did not identify factors associated with the disposal practices followed by participants. The types of unused medicines at home were not identified in this study. As the study was conducted among patients visiting a hospital, the disposal practices described in this study may not represent those of the general community.

Conclusion

Inappropriate disposal of unused medicines was found to be common in the present study. The participants had a gap in their awareness regarding safe disposal practices and potential harm. Hence, healthcare professionals, health authorities and government officials should emphasise awareness creation, provide advice and allocate budgets to ensure the safe disposal of unused medicines as appropriate to people’s circumstances.

Data availability statement

All data relevant to the study are included in the article or uploaded as supplementary information.

Ethics statementsPatient consent for publication

Not applicable.

Ethics approval

This study involves human participants and was approved by Institutional Research and Ethical Review Committee (IRERC), College of Health Sciences, Debre Tabor University (ref: CHS/DTU1484/2022). Participants gave an informed consent to participate in the study before taking part.

Acknowledgments

We thank Debre Tabor University, College of Health Sciences, and Debre Tabor Comprehensive Specialized Hospital for facilitating study completion. We are also grateful to the data collectors for their punctuality and honesty in data collection.