
==== Front
BMC Public Health
BMC Public Health
BMC Public Health
1471-2458
BioMed Central London

20021
10.1186/s12889-024-20021-x
Research
Extent and causes of unused medications among patients in rural Ethiopia: a prospective multicenter cohort study
Gebregeorgise Dawit T. dawit.teshome@aau.edu.et

1
Fenta Teferi Gedif 1
Bemt Bart J. F. Van den 23
Bekker Charlotte L. 3
1 https://ror.org/038b8e254 grid.7123.7 0000 0001 1250 5688 Department of Pharmaceutics and Social Pharmacy, School of Pharmacy, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia
2 https://ror.org/042yqf226 grid.491399.f Department of Pharmacy, Sint Maartenskliniek, Nijmegen, The Netherlands
3 https://ror.org/05wg1m734 grid.10417.33 0000 0004 0444 9382 Department of Pharmacy, Radboud University Medical Center, Nijmegen, The Netherlands
17 9 2024
17 9 2024
2024
24 252726 12 2023
9 9 2024
© The Author(s) 2024
2024
https://creativecommons.org/licenses/by-nc-nd/4.0/ Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.
Background

Medication waste poses health, economic, and environmental challenges. However, the extent among patients living in rural areas is underexplored. This study assessed the proportion of prescribed medications remaining unused by patients living in rural areas of Ethiopia, and identify the causes thereof and disposal practices.

Methods

A prospective multicenter cohort study was conducted in 5 rural health centers in Ethiopia. Patients (≥ 18 years), who received a prescription for acute or chronic medication for pick up from the outpatient pharmacy were included. After 3 months, participants received a house visit by a health employee during which a questionnaire was verbally administered to assess the quantity of unused medication, reason thereof, and disposal practices used. Data were analyzed using descriptive statistics and multivariate logistic regression to identify factors associated with presence of unused medications.

Results

In total, 178 patients participated. Up to 136 out of 601 (22.6%) dispensed medications ended up unused, mainly antibiotics and analgesics, with an average economic value of $0.37. Of 178 patients, 72 (40.4%) ended up with unused medication, and 15 (8.4%) did not use 80% or more of the prescribed quantity. Early discontinuation of therapy was the main reason (61.8%) for patients’ ending with unused medication. Patients reported to primarily dispose of unused medication either through the toilet (43.6%), household garbage (22.7%), burning (13.6%), or returning it to the pharmacy (2.7%). Medications dispensed to be administered with two or more-unit doses at a time were more likely to remain unused (adjusted OR 1.6 [1.0–3.4]) compared to medications dispensed to be administered one-unit dose.

Conclusion

A substantial amount of prescribed medications remains unused by patients in rural areas, frequently not properly disposed. Interventions are needed to ensure medications are not wasted and reduce the unwanted consequences.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-024-20021-x

Keywords

Unused medication
Medication waste
Disposal
Medication beliefs
Sustainability
issue-copyright-statement© BioMed Central Ltd., part of Springer Nature 2024
==== Body
pmcIntroduction

Medication waste is a growing problem, affecting public health, healthcare expenditures and the environment negatively [1–3]. Lost therapeutic benefit, waste of money and environmental contamination as a result of waste might cause additional burden for the attainment of sustainable development goals and universal health coverage particularly in low- and middle-income countries if left neglected [1].

Medication waste is defined as expired or unused medications throughout the whole pharmaceutical supply chain [4]. Studies show that medications that are prescribed for and dispensed to patients are not fully used at home [5–7]. This is due to, for instance, early discontinuation of treatment resulting from improved health condition, intolerable side effects, or a switch in treatment [8–12]. When medications remain unused, most patients do not dispose of them properly, not always by returning them during drug take-back program or following through household disposal steps [13, 14]. They would rather throw it away, put it into the household garbage, or flush it in the toilet, or sink [9, 15].

Accumulation of unused medications at patients’ homes could lead to health [16], economic [17] environmental challenges [18]. For instance, in the US, more than 36,000 children (aged 0–4) get poisoned every year [19], mainly due to ingestions of medications kept at home [16]. Also, various countries report on the financial value of unused medications and its associated loss [7]. Furthermore, unsafe disposal of unused medications poses risks to environment (i.e., in water, on land, and in the air) potentially affecting the ecosystem [18].

From an ecological perspective, around 25% of wastewater streams worldwide are contaminated with excessive high levels of pharmaceuticals. Among these countries, Ethiopia was ranked as top three of highest polluters [20]. While this is primarily due to a lack of enforceable regulatory oversight for proper medication sales [10], resulting in excessive medication use, the impact of improper disposal of unused medications might contribute as well.

Although the risks of pharmaceuticals polluting the environment are more significant in lower-middle income countries (LMICs) [20, 21], studies indicate that most LMICs are less concerned about environmental, health and social impact of unused medications [21]. According to the Sustainable Development Goals (SDGs) of the United Nation [22], increasing access to medications, achieving environmentally sound management of medications, other chemicals and waste throughout their life cycle and reducing the number of deaths and illnesses associated with these are the targets to be achieved.

There is health service coverage inequalities, including medication use, between urban and rural areas [23–25]. The concurrent health, social, economic, humanitarian and human rights crises in rural areas affect primary health care service negatively [25]. Unused medication and its associated risks assumed to be imbalanced in rural areas, making attaining universal health coverage and ensuring equal access to healthcare too far. In Ethiopia, studies have quantified the extent of unused medications (i.e., 50–66%) [26–29] among households, described the reasons for accumulation of unused medications and the commonly used disposal practices [26–32]. However, most of these studies were conducted in urban areas, whereas the majority of the population lives in rural areas where the socio- economy, health seeking behavior and health literacy level are relatively low. In addition, previous studies used cross-sectional designs and lacked numbers of the actual extent of medications enduing up unused. Therefore, this study aimed to prospectively assess the proportion of prescribed medications remaining unused by patients living in rural area of Ethiopia, and identify the causes thereof and disposal practices. Furthermore, patients’ beliefs about medications and pharmaceutical literacy levels were assessed.

Methods

Study design and setting

A prospective multicenter cohort study was conducted in five health centers in rural areas of North Shoa Zone, Amhara Regional State, Ethiopia between April – September 2022. This zone consists of 472 health facilities (i.e., 1 referral hospital, 3 general hospitals, 8 primary hospitals, 97 health centers, and 372 health posts) and 354 health workforces (i.e.,115 general practitioners, 356 health officers, 1,064 nurse, 435 midwifery, 293 laboratory, 395 pharmacy, and 882 health extension workers) serving a total of 2,231,205 people. Acute and chronic diseases are the major health burden of the zone [33].

Study population

Adult patients (≥ 18 years), who filled at least one prescription for common acute and chronic indications (i.e., infection, hypertension, diabetes, asthma, or arthritis), were able to speak the local language (Amharic), and collected medications from the pharmacy of the health facility during the study period, were eligible for inclusion. Patients who were terminally ill or receiving non-orally administered medication were excluded. A consecutive sample of pharmacy visitors receiving a prescription were approached for participation. Eligible patients received information about the study from a health facility employee and were asked to provide verbal consent.

Sample size

The number of medications included in the study were determined using a single population proportion formula;

\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$n=\frac{{{{({z_{\alpha /2}})}^2} \times p(1 - p)}}{{{d^2}}}$$\end{document}

where:

Z is confidence level at 95% (standard value of 1.96).

p is the proportion of patients with unused medications.

d is margin of error.

Previous study shows that 13.8% [30] of the households in the Awi zone, Amhara regional have unused medication. This was assumed to be the same in North Shoa too, which is found in Amhara regional states. Taking this, and a margin of error (d) of 5% and the z (1 − ∝/2) value at 95% confidence interval (CI) i.e., 1.96, the sample size was found to be 183. Considering a non-response rate of 10%, the final sample size was determined to be 201.3 ~ 202 patients. So, 202 patients were followed for three months.

Study instruments and variables

Unused medications record

Unused Medications Record form was adapted and modified from previous study [5] to fit the local context and collect patient related information including demographics, disease and medication related characteristics (see Supplementary materials). Demographics related information included were age, gender, religion, living situation (alone/with family members), and educational level of patients. Similarly, disease related information included were acute vs. chronic of the diagnosed disease and patient-reported perceived seriousness of the illness. Moreover, name, strength, quantity of the prescribed medications and quantity remaining unused (in units i.e., tablets or capsules and packages (unopened) were recorded as medication characteristics.

Beliefs about medications questionnaire

The Beliefs About Medicines Questionnaire (BMQ) is a validated tool for evaluating people’s perception about medications [34]. It has an 18 (i.e., 8 general and 10 specific) item Likert scale ranging from 1 [strongly disagree] to 5 [strongly agree]. BMQ tool was used in this study to evaluate patients’ belief about necessity and concerns of the prescribed medication and their general perception about medication overuse and harm (see Supplementary materials).

Recognizing and addressing limited pharmaceutical literacy (RALPH) interview guide

RALPH interview guide is prepared to support pharmacists in identifying patients with limited pharmaceutical literacy during dispensing and provide tailored medication information to their needs to use their medications safely [35]. In this study, this tool was used to assess patients’ understanding regarding the purpose, frequency and timing of the prescribed medication. The tool was also used to assess patients’ ability to ask questions/express concerns about the prescribed medications to their healthcare providers, and find understandable (medication) information (see Supplementary materials).

Questionnaires were translated to the local language by two researchers independently and compared. The full questionnaire was pilot tested with two patients on the comprehensiveness, and understandability and the time it takes to complete the questionnaire. Accordingly, modifications such removing an item from RALPH question, including detailed information about locality, administering questions in two (i.e.at the time of dispensing and during the house visits) were done. This study follows the ‘Strengthening the Reporting of Observational Studies in Epidemiology’ (STROBE) statement [18].

Study procedure

Patients agreeing to participate were asked demographic information. They were also counselled about the prescribed medication and supplied with a paper bag and received instructions to store the dispensed medication in the bag, including any medicine that was unused following completion or premature discontinuation of treatment regimen. If patients collected new prescriptions within three months, they were instructed to store these in the bag as well. Before leaving the pharmacy, they were asked the purpose, frequency and timing of the prescribed medication to assess their level of understanding. Moreover, their ability to ask healthcare provider questions, express concerns about their medication, and find understandable (medication) information were assessed. Based on patients’ response, the dispensing pharmacists categorized the answers into “correct” and “incorrect”, seek information from a reliable source, or not. Patients, were followed for three months and received a house visit after three months follow-up by a trained data collector. During this house visit, a questionnaire was verbally administered on quantity remaining unused (in units i.e., tablets or capsules and packages [unopened]) and reason for having unused medication (adverse effects, condition resolved, therapy changed, insufficient effect, early discontinuation and pharmacy supplied too much, and other) and disposal practice. The estimated monetary value of dispensed and unused medication were converted to dollars using weighted average exchange rate of the data collection period [36].

Study outcomes

The primary outcome is the proportion of prescribed medications remain unused. This was assessed by asking the patient whether the unused medication was no longer used. If patients reported that the unused medication would be used in the future, this was not considered as unused.

Secondary outcomes included economic value of unused medication, proportion of patients having unused medication, reasons for having unused medication, and frequently used disposal practices. Patients’ beliefs about medications and pharmaceutical literacy, which have direct implication on for sensible use of medication were used.

For the Beliefs about Medicine Questionnaire, the sum for the-sub scale score for necessity (range:5–25), concern (range:5–25), overuse (range:4–20), and harm (range:4–20) of using medication were calculated. The higher the score refers to the stronger belief about medications. The sum scale score for necessity beliefs was subtracted from the sum scale score for concern beliefs to yield the necessity–concerns differential (NCD) score (range: -20–20). A positive NCD score indicates that the necessity domain dominates the concern domain.

For pharmaceutical literacy, two items of the RALPH, which contain correct or incorrect answers regarding the purpose, frequency and timing of the prescribed medication were graded as response and three items which asks how easy/difficult for patients to ask questions and concerns about their medications to the healthcare professionals were evaluated by a pharmacist. Literacy scores were derived by summing the item scores and dividing by the number of items.

Data analysis

Descriptive statistics consisting of median and interquartile range (IQR) for non-normal distributions and mean with standard deviation (SD) for normal distribution, and proportions expressed as percentages were calculated using SPSS version 25 software. Uni- and multivariate logistic regression were used to identify factors associated with unused medication (dependent variable). Independent variables were age, gender, religion, educational level, unit dose, treatment duration, living situation, disease condition and perceived seriousness of the illness. Variables that had a p-value of less than 0.25 in bivariate analysis were retained.

Results

Characteristics of participants

202 patients were approached and included, of which 8 were lost-to follow up due to no longer available. In total, 194 patients were followed for three months and received a house visit. Of these, 178 were included in the analysis and 16 (i.e., seven patients were dispensed dosage forms such as eye drop/injection difficult to measure the leftover objectively; six patients with no recorded of unused medication and three patients with incompletely recorded forms [i.e., more than 50% of the item were not answered] were excluded (Fig. 1). On average, patients were followed for 93.1 days (range 80–114).

Fig. 1 Schematic overview of inclusion of participants

Participants had a median age of 46 years (IQR:33.5–60), and 117 (65.71%) were female (Table 1). Most participants 134 (75.2%) had no formal education and lived with family 151 (84.8%).

Table 1 Demographic characteristics of study participants (n = 178)

Characteristic	n = 178 (%)	
Age (median, IQR)	46 (IQR 33.5–60)	
Gender*	
Female	117 (65.7)	
Male	60 (33.7)	
Religion*	
Orthodox Christian	177 (99.4)	
Muslim	1 (0.2)	
Educational level*	
No education	134 (75.2)	
Primary School (Grade 1–8)	23 (12.9)	
Secondary School (Grade 9–12) and above	15 (8.4)	
Living situation*	
Living alone	23 (12.9)	
Living together with family	151 (84.8)	
Disease condition	
Acute	129 (72.5)	
Chronic	49 (27.5)	
Perceived seriousness of the illness*	
Mild	19 (10.7)	
Moderate	75 (42.1)	
Severe	84 (47.2)	
*missing data

Proportion of medications remaining unused

In total, 601 medications were prescribed to 178 patients, of which 136 (22.6%) remained unused. Of 14,317 capsules and tables dispensed, 1,558 (11%) remain unused. Antibacterial for systemic use 49 (36%) and analgesics 29 (21.3%) were the most commonly unused therapeutic class of medications (Table 2). A total of 72 (40.4%) patients ended up with at least one unused medication. 15 (8.4%) patients ended up with at least 80% of the prescribed medication. Of the total ($428.8) value of the dispensed medication, medications worth $51.1 (11.9%) remained unused (Table 2).

Table 2 Therapeutic class of frequently unused prescribed medication remaining unused (n = 136)

Therapeutic Class	Unused medication n = 136 (%)	
Antibacterial for systemic use	49 (36.0)	
Analgesics	29 (21.3)	
Calcium channel blockers	14 (10.3)	
Corticosteroids for systemic use	14(10.3)	
Drugs for acid related disorders	13(9.6)	
Anti-inflammatory and antirheumatic products	9(6.6)	
Others	8(5.8)	

Causes of unused medications

Of the 136 unused medications, 84 (61.8%) medications, mainly antibiotics for systemic use 46 (33.8%), analgesics 11 (8.0%), and medications prescribed for acid related disorders 11 (8.0%), were discontinued early. In addition, 13 (9.6%) medications dispensed in excess by the pharmacy and 37 (27.2%) medications prescribed “when needed” (e.g., for pain control) were found unused. Medications were discontinued mainly as the patients’ disease condition resolved 61 (44.8%). Adverse effects 14 (10.2%) and change in therapy 15 (11.0%) and insufficient therapeutic effect 8 (5.8%) were also the reasons for the discontinuation of medications.

Medication disposal practice

When patients were asked what they normally do with unused medication, 110 (61.7%) respondents said they dispose of it, 26 (14.6%) patients keep it at home for potential future use and 20 (11%) patients keep it for no purpose. Patients reported to primarily dispose of unused medication either through the toilet 48 (43.6%), household garbage 25 (22.7%), burning 15 (13.6%), or return it to the pharmacy (2.7%).

Beliefs about medications

BMQ scores were analyzed for 106 respondents. Patients’ mean scores regarding the necessity and concern subscales were 16.7 (SD 4.1) and 10.9 (SD 3.0), respectively. The findings revealed a positive necessity-concerns differential (NCD) score of 5.8 (range: -20–20), indicating a dominant belief on the need for using the prescribed medications. Similarly, patients rated mean scores 12 (SD 1.5) for general overuse and 7.5 (SD 2.0) for general harm sub scales. Respondents did not agree with the perception that there is harm associated with medication in general. In contrast, they were uncertain about whether healthcare professionals overprescribe medication to patients or not (Table 3).

Pharmaceutical literacy of respondents

Regarding pharmaceutical literacy, 149 (83.7%) participants correctly answered the purpose for which the prescribed medication issued during study entry was indicated. Also, 157 (88.2%) patients correctly answered the frequency and timing of the prescribed medication. If there was discrepancy in the information given by the healthcare professionals (e.g., between the pharmacist and the physician) about the prescribed medication, 87(48.8%) participants said they would seek information from a reliable source, 31 (15.9%) would do so but not necessarily from a reliable source, and 32 (17.4%) would do nothing. In general, if patients had a question about their prescribed medication, 154 (86.5%) found it easy to ask a healthcare professional.

Table 3 Participants’ score for the general and specific BMQ items (n = 106)

	Mean (SD)	Sub-category
Mean score (SD)	Sub-category
sum score, mean (SD)	
Specific necessity	
My health at present depends on my medicines	3.0 (1.1)	3.3 (0.8)	16.7 (4.1)	
My life would be impossible without my medicines	2.8 (1.2)	
Without my medicines I would be very ill	3.4 (1.2)	
My health in the future will depend on my medicines	2.8 (1.2)	
My medicines protect me from becoming worse	4.4 (0.6)	
Specific concern	
Having to take medicines worries me	2.1 (0.8)	2.2 (0.6)	10.9 (3.0)	
I sometimes worry about long-term effects of my medicine	2.6 (2.0)	
My medicines are a mystery to me	1.9 (0.9)	
My medicines disrupt my life	1.8 (0.9)	
I sometimes worry about becoming too dependent on medicines	2.3 (1.0)	
General overuse		3.0 (0.3)	12.0 (1.6)	
Doctors use too many medicines	2.9 (1.1)	
Natural remedies are safer than medicines	1.6 (0.7)	
Doctors place too much trust in medicines	4.2 (0.5)	
If doctors had more time with patients, they would prescribe fewer medicines	3.1 (0.8)	
General harm		
People who take medicines should stop their treatment for a while every now and again	1.5 (0.6)	1.8(0.4)	7.5 (2.0)	
Most medicines are addictive	2.1 (0.9)	
Medicines do more harm than good	1.7 (0.7)	
All medicines are poisons	2.0 (0.7)	

Factors associated with unused medications

Medications ending up unused were significantly more often administered with two or more unit of doses (i.e., tablets/capsules) (Adjusted OR 1.6 [1.0-2.5]) compared to medication administered with one unit of dose at a time (Table 4).

Table 4 Factors associated with unused medications

Factor	Unused medication
n = 132
n (%)	Used medication
n = 463
n (%)	Crude OR	Adjusted OR	
Age	
18–64	96 (72.7)	376 (81.2)	Ref	Ref	
65+	36 (27.2)	87 (18.7)	1.6 (1.0–2.5)	1.5 (0.9–2.4)	
Gender*	
Female	99 (75.0)	313 (67.6)	1.4 (0.9–2.2)	1.4 (0.9–2.2)	
Male	33 (25.0)	150 (32.4)	Ref	Ref	
Education	
No education	109 (82.5)	355 (76.7)	Ref	Ref	
Had education	23 (19.4)	108 (23.3)	0.6 (0.4–1.1)	0.7 (0.4–1.3)	
Unit dose administered

(tab/caps)

	
1	91 (68.9)	347 (74.9)	Ref	Ref	
2 or more	41 (31.0)	116 (25.1)	1.3 (0.8–2.0)	1.6 (1.0–2.5)	
Treatment duration	
	1–14 days	67 (50.7)	232 (50.1)	Ref	Ref	
	15 days or more	39 (29.5)	113 (24.4)	1.1 (0.7–1.8)	1.1 (0.6–2.5)	
	Unspecified duration	26 (19.6)	118 (25.5)	0.7 (0.4–1.2)	0.6 (0.3–1.1)	
Significant associations are shown in bold; *shows missing sociodemographic data

Discussion

This study quantified the extent of unused medications prescribed to patients living in rural areas in Ethiopia. One-fifth of the dispensed medication remained (partially) unused, and even 40% of patients ended up with unused medication.

This study demonstrated that a substantial number of prescribed medications remained unused within 3 months. When comparing the proportion of patients ending up with unused medication, this is lower than previous research conducted in Ethiopia with ranges of 50–66% of patients [26–29]. This could be explained by the fact that this study consisted of active follow-up over 3-month period, while previous studies included a cross-sectional survey design and asked whether participants experienced any unused medication during any time of treatment. A systematic review done reported 90- 99.6% in middle East countries, 38-94.8 in Asia, 35.0-97.7% in Africa [8]. In Europe, estimates of the share of household medication becoming waste vary from 3% to as high as 50% [37]. Previous research used cross-sectional surveys, visited households and checked availability of any unused medication from all family members and computed unused medications per household, whereas this study used a prospective observational design to objectively measure medication waste.

In terms of economic value, 11.9% of the total value of dispensed medication was wasted. Although these were mainly low-cost medications, the wasted proportion is substantial given the fact that patients in rural areas of low- to middle income countries have difficulties with access to medicines, unnecessary waste should be avoided.

In this study, BMQ scores with respect to the necessity and concern of prescribed medications, as well as perceptions regarding overuse and harm from medication usage was positive. Patients reported a general high belief in the necessity of the medications and in positive effects of the medication. The positive necessity-concern differential indicates that patients’ belief that the advantages of taking medication outweigh than the disadvantages. Research showed that patient beliefs are significantly associated with waste, indicating that patient beliefs could be taken into account when aiming to minimize medication waste [38].

Factors significantly associated with unused medications were unit dose administered and dosage forms. A study conducted in Switzerland showed that patient preference for medication is driven by the appearance (format, shape, size, and color – 44%), number of units per administration (39%), and number of administrations per day (17%). More than half of the patients (67%) in this study preferred tablet formulation. As this finding shows, medications that not preferred by patients might remain unused [39]. In this study, capsules were found more likely to end up unused compared to tablets. Medications administered two or more units at a time were also found more likely to remain unused. When aiming to reduce unused medications, patient’s preference needs to be considered this will increase their adherence medication and safe disposal practices. Medication waste prevention strategies therefore target al.l patients. Currently, little is known regarding perspectives of patients on waste-minimizing measures of LMICs.

Patients and health professionals support is required for interventions to be fully uptaken and work at best. Hence, exploring how unused medication could be recycled and reused need to be explored since it avoids costs of producing another resources and reduces costs of disposing expired medication [40].

Early discontinuation of medication, particularly antibiotics, and their metabolites in the environment could lead to increased antimicrobial resistant microorganisms, increasing the risk of potential transmission of resistant antimicrobials to humans [41, 42]. Air pollution, water contamination and exposure to hazardous compounds are linked to 24% of the global deaths (WHO, 2018). Moreover, these factors pose threats to the health of animals, plants and ecosystems. In order to tackle or prevent wastage throughout the medication supply chain, amongst others, creating awareness and education about proper medication use, and safe disposal is crucial.

The majority of patients reported undesirable disposal practice through, for instance, the toilet or household garbage. This can result in significant environmental and public health risks since some medications are designed to be slowly degradable or resist degradation during passage through a human or animal body and persist in the environment [43].In rural areas, where agriculture is the main source of income, unsafe disposal may introduce medications into the soil, water and air; and be retained in various plant parts. According to Gworek reviews, vegetative plant, particularly those which have roots and leaves, were found to have the highest accumulation of active substances of pharmaceuticals and their metabolites [44]. Building and operating waste treatment systems in developing countries, particularly in rural areas is too expensive. It is therefore actions are needed to reduce or curb the risks associated with unsafe disposal of unused medications. This may include introducing safe medication disposal services and promoting safe medication disposal by involving pharmacists [45].

The findings of this study will have practical implications for regulatory, health facilities, healthcare providers, manufacturers and educational institutions, striving to prevent medication wastage, ensure sustainable and green supply chain. It also helps patients with high tendency of ending up with unused medication to get tailored counselling, enjoy therapeutic benefit, prevent resource from being wasted and environment from being contaminated.

Major strength of this study is the prospective follow-up design to accurately assess the proportion of unused medications. Some limitations should be acknowledged. Questionnaires were administered verbally at home that may have led to participants giving socially desirable answers. However, patients living in rural areas have difficulties with reading and writing and therefore this was the most feasible approach. Patients were selected from health facilities in rural areas and this population may not be comparable with those living in urban areas or other settings.

Conclusion

Sizable amount of medications remains unused by patients living in rural setting at home. Also, almost all medications are being disposed of unsafely. Educational interventions aimed at proper use of prescribed medications and safe disposal of leftovers are needed to tackle this waste to ensure adequate prevention and waste management at patient level to minimize unwanted consequences for public health, healthcare expenditures and environment risks associated with this unsafe disposal practice.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Supplementary Material 1

Supplementary Material 2

Acknowledgements

We would like to thank the participating health centers and patients for their contribution.

Author contributions

All authors participated in the article preparation. DTG was involved in study conceptualization and design, data collection, analysis and interpretation, and drafting the manuscript. CB was involved in study conceptualization, protocol preparation, data interpretation, and reviewing the manuscript. TGF reviewed the manuscript and provided feedback for finalization. BB was involved in study conceptualization and design, data interpretation and reviewing the manuscript. All authors read and approved the final manuscript.

Funding

This research was supported with an unrestricted grant from the Kuehne Foundation.

Data availability

No datasets were generated or analysed during the current study.

Declarations

Ethics approval and consent to participate

This study was approved by the Ethics Committee of the School of Pharmacy, Addis Ababa University [ERB/SOP/369/2021]. Permission to conduct the study was also secured from North Shoa Zonal Health bureau, selected Woredas health bureaus and health centers. After explaining the study’s purpose and anonymity of reporting the results, verbal informed consent was obtained from all voluntary patients prior to participation.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.

Abbreviations

AMR Antimicrobial resistance

BMQ Beliefs about Medicine Questionnaire

LMICs Lower-middle income countries

NCD Necessity–concerns differential

OR Odds Ratio

RALPH Recognize and Address Limited PHarmaceutical literacy

SDGs Sustainable Development Goals

Publisher’s note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
==== Refs
References

1. Hanning SM Hua C Baroutian S Burrell R Taylor M Wright LJ Svirskis D Quantification and composition of pharmaceutical waste in New Zealand J Mater Cycles Waste Manag 2022 24 4 1603 11 35570848
Hanning SM, Hua C, Baroutian S, Burrell R, Taylor M, Wright LJ, Svirskis D. Quantification and composition of pharmaceutical waste in New Zealand. J Mater Cycles Waste Manag. 2022;24(4):1603–11.35570848
2. World Health Organization Global analysis of healthcare waste in the context of COVID-19: status, impacts and recommendations 2022 Geneva World Health Organization
World Health Organization. Global analysis of healthcare waste in the context of COVID-19: status, impacts and recommendations. Geneva: World Health Organization; 2022.
3. West LM Stewart D Cordina M Mixed-methods approach to determine adherence, knowledge and behavioral determinants associated with medication wastage Res Social Adm Pharm 2020 16 5 654 62 31422017
West LM, Stewart D, Cordina M. Mixed-methods approach to determine adherence, knowledge and behavioral determinants associated with medication wastage. Res Social Adm Pharm. 2020;16(5):654–62.31422017
4. West LM Diack L Cordina M Stewart D Applying the Delphi technique to define ‘medication wastage’ Eur J Hosp Pharm 2015 22 5 274 9
West LM, Diack L, Cordina M, Stewart D. Applying the Delphi technique to define ‘medication wastage’. Eur J Hosp Pharm. 2015;22(5):274–9.
5. Bekker CL van den Bemt BJF Egberts ACG Bouvy ML Gardarsdottir H Patient and medication factors associated with preventable medication waste and possibilities for redispensing Int J Clin Pharm 2018 40 3 704 11 29721736
Bekker CL, van den Bemt BJF, Egberts ACG, Bouvy ML, Gardarsdottir H. Patient and medication factors associated with preventable medication waste and possibilities for redispensing. Int J Clin Pharm. 2018;40(3):704–11.29721736
6. Auta A Omale S Shalkur D Abiodun AH Unused medicines in Nigerian households: types and disposal practices J Pharmacol Pharmacother 2011 2 3 195 6 21897719
Auta A, Omale S, Shalkur D, Abiodun AH. Unused medicines in Nigerian households: types and disposal practices. J Pharmacol Pharmacother. 2011;2(3):195–6.21897719
7. Law AV Sakharkar P Zargarzadeh A Tai BW Hess K Hata M Taking stock of medication wastage: unused medications in US households Res Social Adm Pharm 2015 11 4 571 8 25487420
Law AV, Sakharkar P, Zargarzadeh A, Tai BW, Hess K, Hata M, et al. Taking stock of medication wastage: unused medications in US households. Res Social Adm Pharm. 2015;11(4):571–8.25487420
8. Jafarzadeh A Mahboub-Ahari A Najafi M Yousefi M Dalal K Medicine storage, wastage, and associated determinants among urban households: a systematic review and meta-analysis of household surveys BMC Public Health 2021 21 1 1127 34118923
Jafarzadeh A, Mahboub-Ahari A, Najafi M, Yousefi M, Dalal K. Medicine storage, wastage, and associated determinants among urban households: a systematic review and meta-analysis of household surveys. BMC Public Health. 2021;21(1):1127.34118923
9. Tsiligianni IG Delgatty C Alegakis A Lionis C A household survey on the extent of home medication storage. A cross-sectional study from rural Crete, Greece Eur J Gen Pract 2012 18 1 3 8 21879836
Tsiligianni IG, Delgatty C, Alegakis A, Lionis C. A household survey on the extent of home medication storage. A cross-sectional study from rural Crete, Greece. Eur J Gen Pract. 2012;18(1):3–8.21879836
10. Abahussain EA Ball DE Disposal of unwanted medicines from households in Kuwait Pharm World Sci 2007 29 4 368 73 17273906
Abahussain EA, Ball DE. Disposal of unwanted medicines from households in Kuwait. Pharm World Sci. 2007;29(4):368–73.17273906
11. Zargarzadeh AH Tavakoli N Hassanzadeh A A survey on the extent of medication storage and wastage in urban Iranian households Clin Ther 2005 27 6 970 8 16117997
Zargarzadeh AH, Tavakoli N, Hassanzadeh A. A survey on the extent of medication storage and wastage in urban Iranian households. Clin Ther. 2005;27(6):970–8.16117997
12. Kelly F McMillan S Spinks J Bettington E Wheeler AJ You don’t throw these things out:’ an exploration of medicines retention and disposal practices in Australian homes BMC Public Health 2018 18 1 1026 30119656
Kelly F, McMillan S, Spinks J, Bettington E, Wheeler AJ. You don’t throw these things out:’ an exploration of medicines retention and disposal practices in Australian homes. BMC Public Health. 2018;18(1):1026.30119656
13. United States Environmental Protection Agency. How to Dispose of Medicines Properly 2011 [ https://www.epa.gov/sites/default/files/2015-06/documents/how-to-dispose-medicines.pdf
14. Adminstration USFaD. Where and How to Dispose of Unused Medicines 2021 [ https://www.fda.gov/consumers/consumer-updates/where-and-how-dispose-unused-medicines
15. Paut Kusturica M Tomas A Sabo A Disposal of unused drugs: knowledge and behavior among people around the World Rev Environ Contam Toxicol 2017 240 71 104 27115675
Paut Kusturica M, Tomas A, Sabo A. Disposal of unused drugs: knowledge and behavior among people around the World. Rev Environ Contam Toxicol. 2017;240:71–104.27115675
16. Hoy JL Day LM Tibballs J Ozanne-Smith J Unintentional poisoning hospitalisations among young children in Victoria Inj Prev 1999 5 1 31 5 10323567
Hoy JL, Day LM, Tibballs J, Ozanne-Smith J. Unintentional poisoning hospitalisations among young children in Victoria. Inj Prev. 1999;5(1):31–5.10323567
17. Bekker CL Melis EJ Egberts ACG Bouvy ML Gardarsdottir H van den Bemt BJF Quantity and economic value of unused oral anti-cancer and biological disease-modifying anti-rheumatic drugs among outpatient pharmacy patients who discontinue therapy Res Social Adm Pharm 2019 15 1 100 5 29610051
Bekker CL, Melis EJ, Egberts ACG, Bouvy ML, Gardarsdottir H, van den Bemt BJF. Quantity and economic value of unused oral anti-cancer and biological disease-modifying anti-rheumatic drugs among outpatient pharmacy patients who discontinue therapy. Res Social Adm Pharm. 2019;15(1):100–5.29610051
18. Domingo-Echaburu S Davalos LM Orive G Lertxundi U Drug pollution & Sustainable Development Goals Sci Total Environ 2021 800 149412 34391154
Domingo-Echaburu S, Davalos LM, Orive G, Lertxundi U. Drug pollution & Sustainable Development Goals. Sci Total Environ. 2021;800:149412.34391154
19. Schwebel DC Evans WD Hoeffler SE Marlenga BL Nguyen SP Jovanov E Unintentional child poisoning risk: a review of causal factors and prevention studies Child Health Care 2017 46 2 109 30
Schwebel DC, Evans WD, Hoeffler SE, Marlenga BL, Nguyen SP, Jovanov E, et al. Unintentional child poisoning risk: a review of causal factors and prevention studies. Child Health Care. 2017;46(2):109–30.
20. Wilkinson JL, Boxall ABA, Kolpin DW, Leung KMY, Lai RWS, Galban-Malagon C et al. Pharmaceutical pollution of the world’s rivers. P Natl Acad Sci USA. 2022;119(8).
21. Fekadu S Alemayehu E Dewil R Van der Bruggen B Pharmaceuticals in freshwater aquatic environments: a comparison of the African and European challenge Sci Total Environ 2019 654 324 37 30448654
Fekadu S, Alemayehu E, Dewil R, Van der Bruggen B. Pharmaceuticals in freshwater aquatic environments: a comparison of the African and European challenge. Sci Total Environ. 2019;654:324–37.30448654
22. United Nations. THE 17 GOALS n.d [ https://sdgs.un.org/goals
23. Morris-Paxton AA Reid S Ewing RG Primary healthcare services in the rural Eastern Cape, South Africa: evaluating a service-support project Afr J Prim Health Care Fam Med 2020 12 1 e1 7 32242430
Morris-Paxton AA, Reid S, Ewing RG. Primary healthcare services in the rural Eastern Cape, South Africa: evaluating a service-support project. Afr J Prim Health Care Fam Med. 2020;12(1):e1–7.32242430
24. World Health Organization. Imbalances in rural primary care: a scoping literature review with an emphasis on the WHO European Region.; 2018.
25. United Nations Tackling inequalities in public service coverage to build forward better for the rural poor 2021 New York, NY United Nations, Team PbbtHIT
United Nations. Tackling inequalities in public service coverage to build forward better for the rural poor. New York, NY: United Nations, Team PbbtHIT; 2021.
26. Wondimu A Molla F Demeke B Eticha T Assen A Abrha S Melkam W Household Storage of Medicines and Associated factors in Tigray Region, Northern Ethiopia PLoS ONE 2015 10 8 e0135650 26275057
Wondimu A, Molla F, Demeke B, Eticha T, Assen A, Abrha S, Melkam W. Household Storage of Medicines and Associated factors in Tigray Region, Northern Ethiopia. PLoS ONE. 2015;10(8):e0135650.26275057
27. Asmamaw G Agedew T Tesfaye B Sasamo S Gena S Argeta M Adio A Prevalence of leftover medicines, disposal practices, and associated factors in Arba Minch Town, Southern Ethiopia SAGE Open Med 2023 11 20503121231158214 36935887
Asmamaw G, Agedew T, Tesfaye B, Sasamo S, Gena S, Argeta M, Adio A. Prevalence of leftover medicines, disposal practices, and associated factors in Arba Minch Town, Southern Ethiopia. SAGE Open Med. 2023;11:20503121231158214.36935887
28. Ayele Y, Mamu M. Assessment of knowledge, attitude and practice towards disposal of unused and expired pharmaceuticals among community in Harar city, Eastern Ethiopia. J Pharm Policy Pract. 2018;11(1).
29. Kassahun H Tesfaye D Disposal Practices of Unused Medications among Patients in Public Health Centers of Dessie Town, Northeast Ethiopia: a cross-sectional study Curr Drug Saf 2020 15 2 105 10 32228428
Kassahun H, Tesfaye D. Disposal Practices of Unused Medications among Patients in Public Health Centers of Dessie Town, Northeast Ethiopia: a cross-sectional study. Curr Drug Saf. 2020;15(2):105–10.32228428
30. Teni FS Surur AS Belay A Wondimsigegn D Gelayee DA Shewamene Z A household survey of medicine storage practices in Gondar town, northwestern Ethiopia BMC Public Health 2017 17 1 238 28274219
Teni FS, Surur AS, Belay A, Wondimsigegn D, Gelayee DA, Shewamene Z, et al. A household survey of medicine storage practices in Gondar town, northwestern Ethiopia. BMC Public Health. 2017;17(1):238.28274219
31. Kahsay H Ahmedin M Kebede B Gebrezihar K Araya H Tesfay D Assessment of Knowledge, attitude, and Disposal Practice of unused and expired pharmaceuticals in community of Adigrat City, Northern Ethiopia J Environ Public Health 2020 2020 6725423 32351582
Kahsay H, Ahmedin M, Kebede B, Gebrezihar K, Araya H, Tesfay D. Assessment of Knowledge, attitude, and Disposal Practice of unused and expired pharmaceuticals in community of Adigrat City, Northern Ethiopia. J Environ Public Health. 2020;2020:6725423.32351582
32. Woldeyohanins AE, Adugna M, Mihret T, Kifle ZD. Knowledge, Attitude, and Practices of Unused Medications Disposal among Patients Visiting Public Health Centers in Gondar Town, Ethiopia: A Cross-Sectional Study. J Environ Public Hea. 2021;2021.
33. Personal C. 2024.
34. Horne R Weinman J Hankins M The beliefs about medicines questionnaire: the development and evaluation of a new method for assessing the cognitive representation of medication Psychol Health 1999 14 1 1 24
Horne R, Weinman J, Hankins M. The beliefs about medicines questionnaire: the development and evaluation of a new method for assessing the cognitive representation of medication. Psychol Health. 1999;14(1):1–24.
35. Vervloet M van Dijk L Rademakers J Bouvy ML De Smet P Philbert D Koster ES Recognizing and addressing limited PHarmaceutical literacy: development of the RALPH interview guide Res Social Adm Pharm 2018 14 9 805 11 29724680
Vervloet M, van Dijk L, Rademakers J, Bouvy ML, De Smet P, Philbert D, Koster ES. Recognizing and addressing limited PHarmaceutical literacy: development of the RALPH interview guide. Res Social Adm Pharm. 2018;14(9):805–11.29724680
36. National Bank of Ethiopia. Inter-Bank Daily Foreign Exchange Rate 2023 [ https://nbebank.com/inter-bank-daily-foreign-exchange-rate-in-usd/)
37. OECD Management of Pharmaceutical Household Waste: limiting environmental impacts of unused or Expired Medicine 2022 Paris OECD Publishing
OECD. Management of Pharmaceutical Household Waste: limiting environmental impacts of unused or Expired Medicine. Paris: OECD Publishing; 2022.
38. West LM Borg Theuma R Cordina M Health locus of control: its relationship with medication adherence and medication wastage Res Social Adm Pharm 2018 14 11 1015 9 29306720
West LM, Borg Theuma R, Cordina M. Health locus of control: its relationship with medication adherence and medication wastage. Res Social Adm Pharm. 2018;14(11):1015–9.29306720
39. MacKenzie-Smith L Marchi P Thorne H Timeus S Young R Le Calve P Patient preference and physician perceptions of patient preference for oral Pharmaceutical formulations: results from a real-life survey Inflamm Intest Dis 2018 3 1 43 51 30505842
MacKenzie-Smith L, Marchi P, Thorne H, Timeus S, Young R, Le Calve P. Patient preference and physician perceptions of patient preference for oral Pharmaceutical formulations: results from a real-life survey. Inflamm Intest Dis. 2018;3(1):43–51.30505842
40. Kellenberger A, Duca DA, Dan ML, Medeleanu M. Recycling unused midazolam drug as efficient corrosion inhibitor for copper in nitric acid solution. Materials. 2022;15(8).
41. Anwar M Iqbal Q Saleem F Improper disposal of unused antibiotics: an often overlooked driver of antimicrobial resistance Expert Rev Anti Infect Ther 2020 18 8 697 9 32281427
Anwar M, Iqbal Q, Saleem F. Improper disposal of unused antibiotics: an often overlooked driver of antimicrobial resistance. Expert Rev Anti Infect Ther. 2020;18(8):697–9.32281427
42. Stanton IC, Tipper HJ, Chau K, Klumper U, Subirats J, Murray AK. Does environmental exposure to Pharmaceutical and Personal Care product residues result in the selection of antimicrobial-resistant microorganisms, and is this important in terms of. Human Health Outcomes? Environ Toxicol Chem; 2022.
43. United Nations Environment Programme. Environmentally Persistent Pharmaceutical Pollutants (EPPPs) 2022 [ https://www.unep.org/explore-topics/chemicals-waste/what-we-do/emerging-issues/environmentally-persistent-pharmaceutical
44. Gworek B, Kijenska M, Wrzosek J, Graniewska M. Pharmaceuticals in the Soil and Plant Environment: a review. Water Air Soil Poll. 2021;232(4).
45. Coleman M Smith J Powers A Veach S Bishop S Witry M Evaluation of medication disposal behaviors after counseling by a community pharmacist and provision of a home medication disposal kit J Am Pharm Assoc (2003) 2023 63 4S S64 8 36609054
Coleman M, Smith J, Powers A, Veach S, Bishop S, Witry M. Evaluation of medication disposal behaviors after counseling by a community pharmacist and provision of a home medication disposal kit. J Am Pharm Assoc (2003). 2023;63(4S):S64–8.36609054
