Table 1. Summary of articles included in the discussion.

BCTHN, British Columbia take-home naloxone, THN, take-home naloxone; PWID, people who inject drugs; PWUD, people who use drugs; OEND, overdose education and naloxone distribution; OOPP, opioid overdose prevention program

Author (date)	Study purpose	Study design	Summary of key findings relevant to this review
Antoniou et al. [28] (2021)	To assess the experiences of individuals who had accessed naloxone from a community pharmacy, relating these experiences to the risk environments and broader naloxone discourses.	Qualitative in-depth interviews were completed with 37 participants.	Participants experienced stigma when accessing naloxone, feared legal repercussions as well as tapering of opioid doses. Participants preferred less judgmental naloxone distribution sites.
Bachhuber et al. [29] (2015)	To determine the types of messaging that can increase public support for naloxone distribution policies in the United States.	A web-based randomized survey was distributed to an address-based random sampling of households, with 1 598 respondents.	Providing facts about opioid use and/or providing sympathetic narratives to respondents led to higher support for naloxone distribution and laws protecting those administering naloxone.
Bakhireva et al. [30] (2018)	To identify what barriers and facilitators may exist to dispensing intranasal naloxone by pharmacists in New Mexico.	Questionnaires were distributed to pharmacists, with 390 respondents.	Pharmacists surveyed responded that: naloxone administration may lead to continued or riskier opioid use, that distributing naloxone from their pharmacy may bring in clientele that would negatively affect their business, that the cost of naloxone to clients may prohibit access, and that there may be insufficient time to properly train and educate clients on naloxone administration.
Bartlett et al. [31] (2011)	To examine understandings of risk factors related to overdose from a local perspective, assessing ongoing barriers to overdose response, and soliciting input from clients of a harm reduction program in Geiju, China.	30 qualitative interviews were completed in total, comprised of 15 individuals who had overdoses reversed through naloxone injections, and 15 individuals who called the hotline of the harm reduction program in response to witnessing an overdose.	Participants pointed to local changes in heroin use such as the aging of the opioid using population as well as drug mixing practices that increase the risk of overdose. Avoidance of emergency service providers was seen as a result of concerns that medical professionals may be unwilling to treat PWUD, that their confidentiality may not be protected, and that high financial costs associated with treatment function as a barrier to its access.
Beletsky et al. [32] (2007)	To assess the willingness and knowledge of physicians to prescribe naloxone.	A questionnaire was mailed and faxed to a sample of physician members of the American Medical Association, with 588 respondents.	Respondents believe that naloxone administration may lead to continued or riskier opioid use.
Bessen et al. [33] (2019)	To better understand the experiences and opinions of emergency responders and opioid users relating to naloxone use and distribution in New Hampshire.	112 semi-structured interviews were conducted with opioid users and emergency responders.	Respondents believed that access to naloxone may enable increased or riskier use of opioids. As well, they believe that naloxone does not address underlying issues of addiction and that it may prevent people who use opioids from visiting an emergency department following an overdose. Perceived barriers to naloxone access include prohibitively high costs to clients, legal concerns, lack of knowledge of how to administer naloxone, stigma towards people who use opioids, painful withdrawal after being administered naloxone.
Boeri and Lamonica [34] (2021)	To better understand opioid use in suburban communities.	105 interviews and short surveys were conducted on people who use opioids residing in suburban areas in Georgia, Massachusetts, and Connecticut.	Participants’ ability to access naloxone varied greatly in different locations.
Bowles and Lankenau [35] (2019)	Exploring the diffusion process of opioid overdose prevention programs (OOPPs) among persons who inject drugs (PWID).	30 qualitative interviews were completed among PWID in Philadelphia to identify key themes.	Barriers to participating in OOPPs included the belief that training was either too time-consuming or unnecessary. Participants stated hesitance to administer naloxone as the recipient may respond aggressively.
Bounthavong et al. [36] (2019)	To identify the perceived barriers and facilitators to dispensing naloxone among providers after the implementation of a national academic detailing program.	Semi-structured interviews were conducted with 11 participants, consisting of physicians, clinical psychiatric pharmacists, and nurse practitioners.	A barrier identified was the lack of support for homeless program users. Facilitators identified were: creating lists of program users, repeat visits, and face-to-face and one-on-one video conferencing.
Childs et al. [37] (2021)	To identify and better understand the challenges and strategies to expand harm reduction services and engage communities in accepting harm reduction perspectives and services.	Qualitative interviews were conducted with 22 professionals working with people who use drugs.	Respondents found that general harm reduction programs, including those that distribute naloxone, face stigma from multiple sources including law enforcement and the general community.
Chronister et al. [38] (2018)	To evaluate the Overdose Prevention and Emergency Naloxone Project (OPENP) THN program in Australia.	Training for the OPENP was given with baseline, post-training, and in-depth interviews six months following training.	Among trainees, there was fear of legal repercussions for calling emergency services when responding to an opioid overdose.
Deonarine et al. [39] (2016)	To examine perspectives related to the British Columbia take-home naloxone (BCTHN) program held by participants, as well as perspectives of law enforcement relating to naloxone administration by police officers.	2 focus groups were conducted with individuals who had received BCTHN training, 2 in-depth interviews were conducted with experienced BCTHN naloxone administrators, and 2 in-depth interviews were conducted with law enforcement officials.	Respondents believe that naloxone administrators may be reluctant to contact emergency services due to legal repercussions.
Donovan et al. [40] (2020)	To understand perceptions of leaders for pharmacy organizations regarding ways for pharmacies and their staff to optimize naloxone dispensing.	In-depth interviews were conducted with 12 pharmacy leaders.	Facilitators identified include: decreasing stigma towards addiction and opioid use, decreasing hesitancy to offer naloxone to patients, coordination of efforts across pharmacies including training.
Dwyer et al. [24] (2016)	To identify perspectives and experiences of service providers relating to THN programs in Victoria, Australia.	15 in-depth interviews were conducted with service providers who are either involved with THN programs or work in a capacity where they are in contact with people who use opioids.	Service providers interviewed held perspectives that: those administering naloxone will be endangered due to aggressive symptoms from the naloxone recipient experiencing withdrawal, there may be insufficient time to provide clients with naloxone training, and that a lack of knowledge of legal liability related to naloxone prescription and administration can deter both.
Edwards et al. [41] (2017)	To assess attitudes held by pharmacists toward the THN program in Alberta and to identify how better to support pharmacists engagement in the program	A questionnaire was e-mailed to clinical pharmacists registered with the Alberta College of Pharmacists, with 470 responses.	Respondents believed that: stigma from the community acted as a barrier to clients, that naloxone kits are not user-friendly, that naloxone programs were poorly advertised, that there may be insufficient time to properly train clients on naloxone administration, that they may face legal repercussions when dispensing or administrating of naloxone, and that distributing naloxone through their pharmacy may invite clientele that would negatively affect their business.
Freeman et al. [42] (2017)	To assess the willingness of pharmacists in Kentucky to dispense naloxone.	A questionnaire was e-mailed to all licensed Kentucky pharmacists, with 1282 respondents.	Respondents stated that there may be insufficient time to properly train clients on naloxone administration, that naloxone administration may lead to continued or riskier opioid use, and that distributing naloxone through their pharmacy may invite clientele that would negatively affect their business
Gatewood et al. [43] (2016)	To determine barriers to naloxone prescription to third-party contacts of people who use opioids (including family members, friends, bystanders) by medical providers.	10 in-depth interviews and three focus group discussions were completed, collecting data from 30 individuals, including academic physicians and medical students.	Barriers included: the belief that providing naloxone would lead to continued or riskier opioid use in the future, costs of naloxone being prohibitive to clients, and lack of knowledge of legal liability related to naloxone administration.
Gilbert et al. [44] (2020)	To better understand the knowledge and attitudes of pharmacists working in rural community pharmacies regarding naloxone.	All 364 rural community pharmacies in Georgia were contacted by phone and asked about naloxone distribution using a “secret shopper” methodology.	Pharmacists can serve as gatekeepers, can act as barriers or facilitators to access based on knowledge of naloxone, perceptions of those seeking naloxone.
Green et al. [45] (2013)	To explore interventions to reduce deaths from opioid overdoses.	143 in-depth interviews were conducted in total, with the study focusing analysis on 24 interviews with health providers working in emergency departments.	Medical providers interviewed believed that providing naloxone may lead to continued or riskier opioid use.
Green et al. [46] (2017)	To explore pharmacists’, caregivers’, and naloxone consumers’ attitudes towards pharmacy-based THN programs and opioid safety in Massachusetts and Rhode Island.	8 focus groups were conducted.	Respondents believed that clients of THN programs would fear discrimination from pharmacists and not participate in the program. There were suggestions to have a system where clients can indirectly communicate with pharmacists that they need naloxone rather than identify themselves as part of the stigmatized group of people who use drugs.
Green et al. [47] (2020)	To examine experiences obtaining naloxone from community pharmacies, and reactions of stakeholders to communication tools and outreach materials promoting the use of naloxone.	8 focus groups were conducted.	Respondents noted stigma when obtaining naloxone from a pharmacy. Respondents also noted fear of legal repercussions or not being prescribed pain medication in the future.
Gunn et al. [48] (2018)	To assess all existing literature that examines naloxone distribution from the ED.	Systematic review.	Respondents believe the costs of naloxone are potentially prohibitive to clients.
Haggerty and Gatewood [49] (2018)	To explore awareness of opioid overdose, as well as to identify perceptions of naloxone and benefits and barriers to naloxone dispensing and administration by community pharmacies in Virginia.	A paper-based questionnaire was distributed to adults in public locations, with 139 respondents.	Respondents believe that naloxone administration may lead to continued or riskier opioid use
Hammett et al. [50] (2014)	To assess law and policy documents, as well as the knowledge, attitudes, and practices of key stakeholders of those involved in programs supporting PWID in six countries (United States, Russia, Vietnam, China, Canada, and Mexico).	Systematic review	Studies reviewed found that clients of THN programs would fear discrimination from health providers and not participate in the program, that distributing naloxone through their pharmacy may invite clientele that would negatively affect their business, and that the costs of naloxone are potentially prohibitive to clients
Holland et al. [51] (2019)	To explore perceptions of THN in ED settings held by physicians and pharmacists,	25 in-depth interviews were conducted with ED pharmacists and physicians,	Interviewed physicians and pharmacists held perspectives that stigma may function as a barrier to accessing THN, that naloxone administration may lead to continued or riskier opioid use, and that there may be insufficient time to properly train clients on naloxone administration
Lai et al. [52] (2021)	To evaluate if drug use patterns change in response to naloxone availability and to explore individuals’ relationship with naloxone.	A pilot study was conducted with semi-structured interviews conducted with 10 participants.	Naloxone kits were considered easy to obtain as they were made available at no cost and training was provided. Participants suggested naloxone be provided to all people leaving needle exchange or treatment programs, and that mobile outreach programs be implemented.
Lewis et al. [15] (2016)	To evaluate the OEND program of the Baltimore Student Harm Reduction Coalition.	Training for the OEND program was given with pretest and posttest surveys, and follow-up telephone surveys 8 to 12 months later. 113 individuals completed the pretest and posttest surveys. 35 individuals completed the follow-up telephone survey.	The training allowed individuals to become more confident with naloxone administration, and less fear of trouble from law enforcement for doing so.
Mahon et al. [53] (2018)	To explore incoming pharmacy students’ baseline knowledge of and attitudes toward harm reduction to create a curriculum that produces pharmacists able to reduce the harm caused by the opioid crisis.	Questionnaires were distributed to first-year pharmacy students, with 167 respondents.	Many students lacked the knowledge to effectively respond to an opioid overdose and were unfamiliar with naloxone. Some students were unwilling to respond in any way other than calling an ambulance. Many students used stigmatizing language towards people who use opioids and felt that naloxone would enable continued or riskier use of opioids.
Martino et al. [54] (2020)	To identify barriers to prescribing naloxone in an OEND program established in an academic health system.	Mixed methods were used, with a questionnaire completed by 72 respondents, made up of physicians and pharmacists, 34 of which participated in a telephone interview.	Facilitators identified include an increased social normalization and acceptability of naloxone use. Barriers identified include the belief that naloxone will encourage increased opioid use, stigma towards addiction and opioid use, and a lack of naloxone training and education for prescribers
McAuley et al. [55] (2018)	To grow the evidence base of THN by examining the lived experience of THN use.	8 qualitative interviews were completed among individuals who had used naloxone from a THN program to reverse an overdose.	The use of naloxone to reverse an overdose is both an emotionally and practically complex experience. Witnessing withdrawal following an overdose reversal was sometimes distressing, but not seen as a barrier to naloxone use. All participants were willing to apply naloxone.
Meyerson et al. [56] (2020)	To explore the feasibility of establishing a harm reduction intervention program in pharmacies, including the distribution of naloxone.	Surveys were completed by 303 Indiana managing pharmacists.	Barriers to naloxone provision include time constraints and the cost to naloxone recipients.
Mitchell et al. [16] (2017)	To address existing knowledge gaps in literature exploring the experiences of young adults with THN programs, and to identify areas for improvement solicited from participants of Inner City Youth (ICY) Program in Vancouver, British Columbia.	2 focus groups and 5 in-depth interviews were conducted with ICY program participants.	Respondents stated that naloxone kits should be placed in common areas of low-income housing units.
Muzyk et al. [57] (2019)	To examine pharmacists’ attitudes towards naloxone and medications used in the treatment of opioid use disorder.	A systematic review was conducted.	The literature found in the review found some pharmacists were not comfortable providing naloxone education to patients, often as a result of a perceived lack of training on the subject. As well, pharmacists reported not being comfortable dispensing naloxone.
Nielsen et al. [58] (2016)	To explore the level of support for overdose prevention, the barriers and facilitators to naloxone supply, and the level of knowledge about naloxone administration among Australian pharmacists.	An online survey was distributed to community pharmacists across Australia, with 595 responses.	Community pharmacists surveyed state there may be insufficient time to properly train clients on naloxone administration.
Nguyen et al. [59] (2020)	To identify components leading to successful naloxone distribution from pharmacies, to evaluate the perceptions held by pharmacy staff regarding those who receive naloxone, and to assess relationships between these perceptions and the distribution of naloxone from pharmacies.	Semi-structured interviews were conducted with 14 pharmacists and pharmacy technicians across pharmacies in San Francisco.	The cost of naloxone was identified as a barrier to access. Establishing the community pharmacy as an encouraging, nonjudgmental environment was discussed as a means of addressing stigma.
Olsen et al. [60] (2019)	To examine the attitudes and experiences of Australian pharmacists regarding dispensing naloxone without patients needing a prescription.	Semi-structured interviews were conducted with 37 community pharmacists.	System-level barriers to dispensing naloxone identified include lack of education and training for dispensing naloxone, supply issues, lack of notification of changes in drug scheduling. Other barriers identified include stigma towards drug use, pharmacists unwilling to take extra time to educate staff and patients, the belief that dispensing naloxone would attract undesirable clientele.
Punches et al. [61] (2020)	To assess perceptions held by emergency nurses regarding take-home naloxone.	In-depth interviews were completed with 17 participants,	Some participants believed that naloxone enabled and condoned risky opioid use.
Richert [62] (2015)	To assess how people who use heroin understand the overdoses of others and make sense of their own and others’ responses to witnessing an overdose.	In-depth interviews were conducted with 35 Swedish heroin users.	Respondents believe that naloxone administrators may be reluctant to contact emergency services due to legal repercussions.
Rudolph et al. [63] (2018)	To identify barriers and areas for additional training in the dispensing of naloxone in community pharmacy settings.	An internet-based questionnaire was distributed to community pharmacists in North Carolina, with 423 respondents.	Community pharmacists remarked that naloxone administration may lead to continued or riskier opioid use and that the costs of naloxone are prohibitive to clients.
Samuels et al. [64] (2016)	To assess perceptions of opioid harm reduction interventions and willingness to perform them among ED physicians.	A web-based survey was distributed to ED physicians, of which there were 200 respondents.	Surveyed pharmacists believed that there may be insufficient time to properly train clients on naloxone administration.
Schneider et al. [65] (2021)	To assess knowledge of locations of accessible naloxone and perceived ease of accessing naloxone among suburban people who use opioids.	Computer-assisted self-interviews were conducted with 171 respondents.	Having knowledge of multiple sites of naloxone distribution and previous access increased ease of access among participants. Distance from harm reduction programs may make access more difficult.
Sisson et al. [66] (2019)	To better understand barriers that may prevent the use of naloxone programs operating out of pharmacies in Alabama.	Telephone surveys were conducted with 222 pharmacists across rural and urban areas in Birmingham, Alabama.	Perceived barriers to uptake of naloxone service include the high cost to patients and pharmacies and the belief that providing naloxone will lead to riskier opioid use.
Tewell et al. [67] (2018)	To describe the establishment of a pharmacist-led clinic where individuals in need of naloxone can be identified, provided education about risks and treatment of opioid overdose, and given naloxone.	During the pilot implementation, discussions were had with patients about their experiences.	Perceived barriers to naloxone access include lack of access to transportation, denial of the need to participate in the program, and stigma toward opioid use.
Thakur et al. [68] (2020)	To examine the roles of pharmacists, barriers, and pharmacist training, for dispensing naloxone from pharmacies.	A systematic review was conducted.	The following perceived barriers to dispensing naloxone identified: lack of training on how to identify and educate patients at risk of opioid overdose, prohibitive cost to patients, belief that dispensing naloxone encouraged opioid abuse, and belief that dispensing naloxone attracted an undesirable clientele.
Thompson et al. [69] (2018)	To examine Ohio pharmacists’ knowledge of naloxone, perceived barriers to naloxone dispensing, as well as confidence, comfort, and experience dispensing naloxone.	E-mail questionnaires were distributed to Ohio pharmacists, with 170 responses	Respondents surveyed believe that naloxone administration may lead to continued or riskier opioid use, that distributing naloxone through their pharmacy may invite clientele that would negatively affect their business, and that naloxone administration does not lead to compensatory or riskier opioid use.
Tobin et al. [70] (2009)	To evaluate the Staying Alive (SA) OEND program in Baltimore, Maryland.	Training for the SA program was given with pretest and posttest surveys, which were completed by 85 trainees.	Among trainees, there was fear of legal repercussions for calling emergency services when responding to an opioid overdose.
Tofighi et al. [71] (2021)	To assess attitudes and experiences of community pharmacists related to provisioning naloxone in non-urban areas of New York State.	Semi-structured surveys were provided to 60 community pharmacists.	A minority of participants believed that naloxone provision increased opioid use.
Young et al. [72] (2019)	To better understand the perceptions of those involved with the rapid increase of naloxone kit production and distribution as part of the British Columbia Take Home Naloxone (BCTHN) program, in terms of the challenges, facilitators, and successes they experienced.	Focus groups and key informant interviews were conducted with 18 stakeholders from a variety of groups involved in the ramp-up of the BCTHN program.	Facilitators identified include increasing the supply of naloxone, changing drug scheduling of naloxone, and addressing stigma toward drug use
Zaller et al. [73] (2013)	To examine the feasibility of implementing pharmacy-based THN programs in Rhode Island.	In-depth interviews were conducted with 21 PWID and 21 pharmacy staff.	Respondents perceived both THN clients and pharmacists as not being willing to participate in the program. As well, respondents believed the costs of naloxone are potentially prohibitive to clients.