Patients’ knowledge, attitudes and concerns regarding the disposal of expired/unused medication

Abstract

Objectives

Unused/expired medicines that are improperly disposed of can enter soil and water supply and have negative implications for public health. This study aimed to assess patients’ knowledge and understanding of medication disposal practices and their willingness to participate in a medication takeback programme.

Methods

A self-administered questionnaire comprising of 26 questions based on demographics, knowledge, beliefs, practices and concerns was utilized in this study. The study was conducted over 12 weeks at outpatient pharmacy sites located in the four Regional Health Authorities in Trinidad. Statistical Package for the Social Sciences (SPSS) version 24 was used for statistical analysis.

Key findings

A total of 547 persons completed the questionnaire. Knowledge of the dangers of improper medication disposal was highest in those aged 18–25 years (P = 0.007) and having secondary/tertiary level education (P = 0.002). Disposal of unused/expired medication via household thrash (86.1%) was the most commonly encountered practice. Only 14.1% (n = 77) of respondents asked the pharmacist for advice on best disposal practice, although 47.3% (n = 259) thought that the pharmacist should be the main source of advice for information on medication disposal practices. There was a willingness to participate in a medicine takeback programme from 82% (n = 449) of the respondents, and the majority (67.5%) (n = 303) would prefer it if medication takeback programmes were implemented at private community pharmacies.

Conclusions

Patients in Trinidad utilized household garbage as their main disposal method. There is a need to implement a medication takeback programme and educate the public on proper medication disposal.

medicines waste, health promotion, pharmaceutical public health, patient attitudes

Introduction

Trinidad and Tobago (T&T) is the southernmost country of the Caribbean islands covering 5128 km² (1979 sq. mi). In T&T, medications are accessed through private hospitals, community pharmacies, public hospitals and health centre pharmacies, serving approximately 1.4 million citizens. Public hospital and health centre pharmacies are managed by the government and provide medication free of charge for a variety of patients including in-patients, outpatients and specialized clinics.^{[1, 2]} There are approximately 400 private community pharmacies in T&T facilitating medication access. In T&T, 248 privately owned pharmacies operate a state-implemented programme, the Chronic Disease Assistance Programme (CDAP), addressing non-communicable diseases. The programme supplies 47 approved drugs free of charge to the citizens of T&T, with the cost of these drugs increasing from 7.1 to 10.2 million T&T dollars during the fiscal year 2019–20.^[3]

While medication may be easily accessible, not all medication is consumed. For example, it may be discontinued due to intolerable adverse effects; there may be non-adherence to drug regimen, changes in drug dosage or drug treatment; or it may have passed its expiry date. Studies conducted in the USA suggest that a substantial proportion of the population, approximately 46 million Americans, drink water contaminated with trace amounts of pharmaceuticals, including mood stabilizers, anticonvulsants, antibiotics and hormones.^[4]Experimental data from 24 states in the USA discovered that small amounts of antibiotics and hormones were found in the aquifer water located near sources of contamination (e.g. animal feedlots and landfills).^{[4, 5]}

Flushing unused medication down the toilet, washing it down the sink^[6] and disposal in household trash^[7] are also suggested as possible causes of the contamination. Pharmaceutical contamination of the environment is associated with abnormal physiological processes, reproductive impairment, increased incidences of cancer and the development of antibiotic-resistant bacteria.^[8] Taken together, all this creates a risk to the environment, health of humans and ecosystems.^[9]

The primary method of medicine disposal utilized by the public facilities in T&T is incineration.^[10] A Joint Select Committee on Local Authorities, Service Commissions and Statutory Authorities in 2019, estimated the value of expired drugs in T&T disposed of through authorized public sector schemes to be 1.8% of the overall pharmaceutical budget annually, when compared with the global standard of 5%.^[11] These data, however, do not include the expired/unused medications that remain in the possession of the patients or are otherwise disposed. The inappropriate disposal of unused medications represents an avoidable source of pharmaceutical contamination of the ecosystem. This study aimed to assess patients’ knowledge and understanding of medication disposal practices and their willingness to participate in a medication takeback programme.

Method

This study was granted Ethical exemption from the Ethics Committee (CEC113/05/19), University of the West Indies, St Augustine. Approval to conduct the study at various sites was granted from the Ethics Committees of North West Regional Health Authority (NWRHA), North Central Regional Health Authority (NCRHA), Eastern Regional Health Authority (ERHA) and the South West Regional Health Authority (SWRHA).

The study was conducted over a period of 12 weeks using a self-administered questionnaire using systematic random sampling. The questionnaire was developed by the study team based on extensive literature review and by modifying survey questions from the study of Sonowal et al.^[12] and Al-Shareef et al.^[13] The questionnaire was reviewed by two pharmacologists and two members of the pharmacy practice team. The group developed and revised individual questions to ensure simplicity within the local setting so that they could be understood by a lay population regardless of their socioeconomic background.

The questionnaire was divided into four sections consisting of 26 questions. Section A consisted of four short answer/multiple-choice questions on demographics such as gender, age, ethnicity and educational level. Section B consisted of five ‘yes/no’ questions to assess participants’ knowledge of medication waste and its impact on the environment.

Section C consisted of 6 questions using a Likert scale to assess the participant’s perceptions on unused and expired pharmaceuticals, and section D comprised 11 multiple-choice questions on their disposal practice of unused and expired medications. A pilot study was conducted on 50 randomly selected participants, and based on feedback received, questions were further modified to ensure simplicity, clarity and understanding. The average time taken to complete and return the questionnaire was approximately 10 min. A copy of the final questionnaire is presented in the Supplementary Material.

The hospitals within each Regional Health Authority (RHA) facilitate larger patient flow, and in an attempt to capture a wider cross-section and larger portion of the population, the hospitals within each RHA were chosen as the research sites in this study. Eligible participants were persons aged 18 years and older who visited the outpatient pharmacy at any of the selected hospital research sites. The questionnaires were distributed by four study researchers who were final year students in the BSc Pharmacy programme, School of Pharmacy, The University of the West Indies, St Augustine Campus. The researchers approached every fifth patient entering the Pharmacy area. They introduced themselves and informed the potential participant about the purpose of the study. After obtaining verbal and written consent to participate, the researcher explained the meaning of a ‘medication takeback’ programme. The participant was allowed to self-complete the questionnaire without interruption. The survey was conducted during the period 2 August to 2 November 2019.

The population of T&T at the time of this study in 2019 was approximately 1.36 million. The sample size for this study was determined to be 384 persons using a margin of error of 5% and confidence interval of 95%.

The researchers collected the questionnaire immediately after the participant had completed it. Data were entered by two fourth-year pharmacy students and reviewed for quality assurance by the two pharmacologists on the research team by double data entry for a random sub-sample of 125 questionnaires. Statistical analysis was carried out using Statistical Package for the Social Sciences (SPSS) (IBM SPSS Statistics, New York, NY, USA) version 24. Descriptive statistics were used to summarize patients’ knowledge and understanding of medication disposal practices and their willingness to participate in a medication takeback programme. Chi-square analysis was used to detect a significant association between demographics and measured variables. A P-value < 0.05 was considered significant.

Results

During the survey period, 547 persons responded to the survey within the four RHAs in Trinidad for a response rate of 91.17%. The majority of respondents were female (67.6%), 41.1 % were aged 18–35 years and 53.2% had acquired a tertiary level education. The data regarding the demographics of the study population are displayed in Table 1.

Table 1

Demographic data of participants from the different RHA study areas (n = 547)

Demographics	Frequency (%)
	NWRHA (n = 163)	NCRHA (n = 127)	ERHA (n = 53)	SWRHA (n = 204)	Total (n = 547)
Gender
Male	111 (20.3)	90 (16.5)	33 (6.0)	136 (24.9)	370 (67.6)
Female	52 (9.5)	37 (6.8)	20 (3.7)	68 (12.4)	177 (32.4)
Age
18–25	74 (13.5)	54 (9.9)	15 (2.7)	82 (15)	225 (41.1)
26–35	49 (9)	42 (7.7)	12 (2.2)	59 (10.8)	162 (29.6)
36–45	24 (4.4)	20 (3.7)	12 (2.2)	35 (6.4)	91 (16.6)
46–55	13 (2.4)	8 (1.5)	5 (0.01)	25 (4.6)	51 (9.3)
56–65	3 (0.01)	2 (0.004)	9 (0.02)	1 (0.002)	15 (2.7)
>65	0 (0.0)	1 (0.002)	0 (0.0)	3 (0.01)	4 (0.01)
Ethnicity
East Indian	96 (17.6)	85 (15.5)	29 (5.3)	142 (22.7)	352 (64.4)
African	35 (6.4)	27 (4.9)	13 (2.4)	35 (6.4)	110 (20.1)
Mixed	32 (5.9)	15 (2.7)	12 (2.2)	26 (4.8)	85 (15.5)
Education
Primary	8 (1.5)	2 (0.004)	4 (0.01)	12 (2.2)	26 (4.8)
Secondary	60 (11)	56 (10.2)	24 (4.4)	90 (16.5)	230 (42)
Tertiary	95 (17.4)	69 (12.6)	25 (4.6)	102 (18.6)	291 (53.2)

Over-the-counter medications accounted for a high percentage of unused/expired medications, whereas antibiotics were kept by 24.9% (n = 136) of respondents (Table 2). More than three-quarters (86.5%) (n = 473) of patients reported that they had never received information on how to dispose of their unused/expired medication from healthcare workers (Table 3).

Table 2

Types of unused/expired medication in the household of Trinidadian patients (n = 547)

Medication type	Number of participants (%)
Paracetamol	225 (41.1)
Vitamins	248 (45.3)
Antibiotics	136 (24.9)
Painkillers	203 (37.1)
Cough syrup	198 (36.2)
Antacids	91 (16.6)
Diabetes	26 (4.8)
Cardiac	31 (5.7)
High blood pressure	38 (6.9)
Antidepressants	2 (0.4)
None	106 (19.4)

Table 3

Patient perception of education on safe disposal of medications

Study area	NWRHA (n = 163) n (%)	NCRHA (n = 127) n (%)	ERHA (n = 53) n (%)	SWRHA (n = 204) n (%)	Total (n = 547) n (%)
No advice	144 (88.3)	106 (83.5)	41 (77.4)	182 (89.2)	433 (86.5)
Advice given	19 (11.7)	21 (16.5)	12 (12.6)	22 (10.8)	65 (13.5)
Asked for advice	27 (16.6)	15 (11.82)	4 (7.5)	37 (18.1)	83 (15.2)
Pharmacist did not provide information	160 (98.2)	125 (98.4)	52 (98.1)	194 (95.1)	531 (97.1)
Proper guidance would improve outcome	162 (99.4)	125 (98.4)	49 (92.5)	201 (98.5)	537 (98.2)

Almost three-quarters of respondents (70.6%) (n = 386) had no concerns about their method of medication disposal, while 34.7% (n = 190) were concerned about accidental ingestion by children. Only 15.2% (n = 83) asked healthcare workers about the proper disposal methods of unused or expired medication. Respondents believed that the pharmacist did not provide enough information (97.1%) (n = 531) on safe disposal methods, and 98.2% (n = 537) strongly agreed that proper guidance could reduce the amount of unused/expired medication (Table 3). Only 2.9% (n = 16) of the sample population got information on medication disposal from the pharmacist, but there were no statistical differences between the regions (P = 0.161), age groups (P = 0.806) and gender (P = 0.611) for receiving information from the pharmacists on how to dispose of unused/expired medications.

The majority of patients (86.1%) (n = 471) disposed of expired/unused medication by throwing it away in household garbage. Most (70.6%) (n = 386) had no concern about their current method of medication disposal. The internet (19.4%) (n = 106) was the main source of information for medication disposal with pharmacists being the second main source (14.1%) (n = 77), but 67.1% (n =367) had no source of information (Table 4).

Table 4

Disposal practices, concerns, source of information and preferred drop-off points of expired medications among patients in Trinidad (n = 547)

Disposal methods of unused/expired medication (n = 547)	Number of participants (%)
Burn	12 (2.2)
Return to pharmacy	15 (2.7)
Give to relatives/friends	23 (4.2)
Flush down toilet	33 (6.0)
Don’t know what to do	44 (8.0)
Pour down sink	73 (13.3)
Throw in household garbage	471 (86.1)
Patients concerns for medication disposal practices (n = 547)	Number of participants (%)
Swallowed by children	190 (34.7)
Taken from garbage	216 (39.5)
Contaminate water supply/environment	255 (46.6)
No concern	386 (70.6)
Current source of medication disposal information for patients (n = 547)	Number of participants (%)
Nurses	8 (1.5)
Television	24 (4.40
Doctors	33 (6.0)
Pharmacists	77 (14.1)
Internet	106 (19.4)
None	367 (67.1)
Preferred location to drop off unused, expired or unwanted medication (n = 547)	Number of participants (%)
Hospital	163 (29.8)
Health centre	155 (28.3)
Private pharmacy	369 (67.5)
Supermarket	61 (11.2)
Not interested	31 (5.7)

Of all the respondents, 82% (n = 449) would return unused/expired medication to a ‘medication takeback programme’ if it were available, but only 31% (139) would be willing to pay a fee for the proper disposal of unused or expired medication. For patients willing to participate in a medication takeback programme, the majority preferred private community pharmacies (67.5%) (n = 303) as the location to drop off unused or expired medication but 58.1% (n = 261) would also utilize government health facilities as drop-off locations (Table 4).

Knowledge of the risks of inappropriate medicine disposal

Over two-thirds, 70.4% (n = 385) thought that unused or expired medications can be considered as waste, and there was no statistical difference between the regions (P = 0.741), age groups (P = 0.067) and education level (P = 0.122). Of the sample population, 47.2% (n = 258) believed that improper disposal of antibiotics could get into the soil and water, which could pose problems to the environment and increase the incidence of antimicrobial resistance. There were no differences between gender (P = 0.067) and education level (P = 0.304), but a statistically significant difference was seen between the regions (P = 0.015). Of the sample, population from within the NWRHA (70%) and SWRHA (63.7%) believed that antibiotics getting into the soil and water would pose a challenge, while participants from within the ERHA (9.7%) and NCRHA (23.2%) did not.

The inability of water and sewage treatment to remove medical impurities was acknowledged by 50.3% (n = 275) of the sample population. There was no statistically significant difference across regions (P = 0.977). Although 68.4% (n = 374) of the sample population believed that improper medication disposal may have a negative impact on the environment, no statistical differences were seen across regions (P = 0.111), but differences were seen between the age group of 18–25 years (P= 0.007) and education level (P = 0.002). Knowledge level was lower with those of primary level education (50%) when compared with secondary (68.7%) and tertiary (69.8%) levels.

Discussion

The majority of the study population disposed of their unused medication by throwing it in the household garbage. The major concern of improperly disposed medication was accidental overdose in children, with little concern about the effect on people, animals and the environment. The majority of the patients had unused over-the-counter medications and antibiotics in their possession. The internet was the main source of information on proper medication disposal. There was a willingness to participate in a medication takeback programme, with almost one-third willing to pay for the service and preferring private community pharmacies as the drop-off point.

Limitations

The study utilized a cross-sectional approach and targeted the major hospital institutions within each RHA to capture a wide variety of patients. Sampling at hospital sites did not capture the views of those who are based in the various health facilities throughout the country. Persons who do not visit these institutions were not sampled, and, therefore, there may be practices within the community that were not reported. The study team was unable to identify the factors associated with the knowledge and understanding of medication disposal practices within the sample population.

In Trinidad, 86.1% of the respondents disposed of unused or expired medications in the household garbage, which is comparable to what was found in Saudi Arabia^[13] (79.15%), Kabul^[14] (77.7%), New Delhi^[15] (73%), Brazil^[16] (66%), Colombia^[17] (89.8%), Serbia^[18] (85.6%), Ghana^[19] (89%), Australia^[20] (66.7%) and Indonesia^[21] (82.1%).

Pouring unwanted medication down the sink was adopted by 13.3% of Trinidad’s population, which was lower than Australia^[20] (25%), Ireland^[22] (17%) and Tanzania^[23] (41.4%). Only a minority of the Trinidadian public (2.2%) burnt unused/expired medications, also seen in Ethiopia^[24] (3.3%) and Ghana^[25] (19.6%). A small proportion of patients (4.2%) in Trinidad preferred to give their unused medication to a friend, a practice also seen in Ghana^[25] (5.6%). Among pharmacy and nursing students in Saudi Arabia,^[26] 78.9% of pharmacy students and 80.5% of nursing students discard expired medicine in household garbage or flush it down a sink or toilet.

About half (53.2%) of the respondents thought that the environment would be contaminated with improper medication disposal. This was lower than the findings in Brazil^[16] (95.2%) and Colombia^[17] (89.4%), emphasizing the need for public education.

There is a willingness to participate in a medication takeback programme (82%) with 31% willing to pay a fee. Funding for the collection and treatment of household medication waste in European countries^[22] and Australia^[20] comes from either their governments or their pharmaceutical industries. Of the Trinidadian population willing to participate in the medication takeback programme, 67.5% preferred to drop of their unused/expired medications at private pharmacies, which was also seen in a study conducted in Southern California^[27] that reported 70% of respondents were in favour of this drop-off point.

Failure to complete a course of antibiotic treatment can contribute to antimicrobial resistance, and 24.9% had antibiotics in their possession, similar to patients in Tanzania^[23] where 64.1% had antibiotics in their possession for future use. Patients in Trinidad (37.1%) and Ghana^[25] (21.8%) kept painkillers for future use. It highlights the importance of the pharmacist in counselling patients about the dangers of non-adherence.

In Trinidad, 67.1% (n = 367) had no source of information,19.4% (n = 106) would source information from the internet and 14.1% (n = 77) from the pharmacists. In Ethiopia,^[24] 72.5% of the respondents obtained information from their doctors, but in Trinidad, doctors accounted for only 6.0%. In Trinidad, 57% (n = 312) of the respondents thought that there is a lack of medication disposal information with 79.1% in Brazil^[16] agreeing to this. This suggests that more education and awareness are needed to ensure the safe disposal of unused/expired medications.

Stocking excess medications can increase the chance of having expired or unused medications, which can create a problem of accidental poisoning. Pillai et al.^[28] investigated the incidence of acute poisoning in Northern Trinidad and found that 21.8% were cases of accidental poisoning by drugs and that 69.2% of the accidents involved children less than 4 years old.

As much as 50% of wasted medications is due to patients’ non-adherence to medication taking,^[29] which leads to the stockpiling of drugs in the household. Sleep aids and narcotic pain killers in the household have the potential for abuse and can be a source of accidental poisoning children and toddlers.^[30] This danger has been highlighted among parents of pediatric patients with cancer^[31] with opioids, which showed that 90% of parents did not store it safely and 14% did not dispose of opioids properly.

The US FDA has proposed guidelines to assist patients in the safe disposal of unused medication. Where there is no takeback programme readily available, the US FDA has a flush list for drugs that have the potential for abuse and may be fatal if ingested, for example, fentanyl, diazepam and hydrocodone,^[32] that is, they can be flushed down the toilet. For drugs that are not listed for flushing, there are guidelines on how to properly dispose of these medications in the garbage.^[32] With the lack of research in Trinidad to highlight the dangers of improper medication disposal, medication takeback may not be viewed as an urgent matter in planetary health. Despite the lack of data, the impact on the environment has been documented worldwide, and, as such, pharmacist-led medication takeback programmes should be implemented in Trinidad to ensure proper disposal of unused/expired medications by incineration. Further work should be conducted to determine pharmacist knowledge of proper disposal practices, and analysis of soil and water samples should be examined to determine if pharmaceuticals are detected in the environment.

Conclusion

Public education campaigns need to be instituted in Trinidad by health governing bodies to educate the general public of the dangers associated with improper medication disposal. The sample population showed a positive perspective towards medication disposal, but it seems that without a programme to actually dispose of medications properly, patients utilize the easiest method available. This lack of awareness of the appropriate methods for medication disposal provides an opportunity for the pharmacist to lead initiatives for the safe disposal of unwanted household medications in Trinidad. Along with the implementation of this programme, awareness, education and eco-pharmacovigilance need to be addressed. The pharmacist as the drug expert is in an ideal position to engage in patient education and promote programmes to curtail bad practices, which will eventually be of benefit to humans, society and environment.

Author Contributions

Conceptualization: S.J. and N.B.; methodology: S.J., A.V.S., S.H. and K.S.; formal analysis: S.J., S.H., K.S. and V.D.; data curation: S.J., A.V.S., S.H., K.S., N.B. and V.D.; writing – original draft preparation: S.J., N.B. and S.H.; writing – review and editing: A.V.S. and K.S.; visualization: S.J., V.D., N.B. and K.S.; supervision: S.J. and A.V.S. All authors had complete access to the study data that support the publication. All authors have read and agreed to the published version of the manuscript.

Funding

This research was not funded by a specific grant from any funding agency in the public, commercial or not-for-profit sectors.

Conflict of Interest

The authors declare no conflict of interest.