Use of naloxone nasal spray 4 mg in the community setting: a survey of use by community organizations

Comparison of intranasal naloxone and intranasal nalmefene in a translational model assessing the impact of synthetic opioid overdose on respiratory depression and cardiac arrest

Introduction

Using a validated translational model that quantitatively predicts opioid-induced respiratory depression and cardiac arrest, we compared cardiac arrest events caused by synthetic opioids (fentanyl, carfentanil) following rescue by intranasal (IN) administration of the μ-opioid receptor antagonists naloxone and nalmefene.

Methods

This translational model was originally developed by Mann et al. (Clin Pharmacol Ther 2022) to evaluate the effectiveness of intramuscular (IM) naloxone. We initially implemented this model using published codes, reproducing the effects reported by Mann et al. on the incidence of cardiac arrest events following intravenous doses of fentanyl and carfentanil as well as the reduction in cardiac arrest events following a standard 2 mg IM dose of naloxone. We then expanded the model in terms of pharmacokinetic and µ-opioid receptor binding parameters to simulate effects of 4 mg naloxone hydrochloride IN and 3 mg nalmefene hydrochloride IN, both FDA-approved for the treatment of opioid overdose. Model simulations were conducted to quantify the percentage of cardiac arrest in 2000 virtual patients in both the presence and absence of IN antagonist treatment.

Results

Following simulated overdoses with both fentanyl and carfentanil in chronic opioid users, IN nalmefene produced a substantially greater reduction in the incidence of cardiac arrest compared to IN naloxone. For example, following a dose of fentanyl (1.63 mg) producing cardiac arrest in 52.1% (95% confidence interval, 47.3-56.8) of simulated patients, IN nalmefene reduced this rate to 2.2% (1.0-3.8) compared to 19.2% (15.5-23.3) for IN naloxone. Nalmefene also produced large and clinically meaningful reductions in the incidence of cardiac arrests in opioid naïve subjects. Across dosing scenarios, simultaneous administration of four doses of IN naloxone were needed to reduce the percentage of cardiac arrest events to levels that approached those produced by a single dose of IN nalmefene.

Conclusion

Simulations using this validated translational model of opioid overdose demonstrate that a single dose of IN nalmefene produces clinically meaningful reductions in the incidence of cardiac arrest compared to IN naloxone following a synthetic opioid overdose. These findings are especially impactful in an era when >90% of all opioid overdose deaths are linked to synthetic opioids such as fentanyl.

High-dose naloxone formulations are not as essential as we thought

Naloxone is an effective FDA-approved opioid antagonist for reversing opioid overdoses. Naloxone is available to the public and can be administered through intramuscular (IM), intravenous (IV), and intranasal spray (IN) routes. Our literature review investigates the adequacy of two doses of standard IM or IN naloxone in reversing fentanyl overdoses compared to newer high-dose naloxone formulations. Moreover, our initiative incorporates the experiences of people who use drugs, enabling a more practical and contextually-grounded analysis. The evidence indicates that the vast majority of fentanyl overdoses can be successfully reversed using two standard IM or IN dosages. Exceptions include cases of carfentanil overdose, which necessitates ≥ 3 doses for reversal. Multiple studies documented the risk of precipitated withdrawal using ≥ 2 doses of naloxone, notably including the possibility of recurring overdose symptoms after resuscitation, contingent upon the half-life of the specific opioid involved. We recommend distributing multiple doses of standard IM or IN naloxone to bystanders and educating individuals on the adequacy of two doses in reversing fentanyl overdoses. Individuals should continue administration until the recipient is revived, ensuring appropriate intervals between each dose along with rescue breaths, and calling emergency medical services if the individual is unresponsive after two doses. We do not recommend high-dose naloxone formulations as a substitute for four doses of IM or IN naloxone due to the higher cost, risk of precipitated withdrawal, and limited evidence compared to standard doses. Future research must take into consideration lived and living experience, scientific evidence, conflicts of interest, and the bodily autonomy of people who use drugs.

Clinical Pharmacokinetics and Pharmacodynamics of Naloxone

Naloxone is a World Health Organization (WHO)-listed essential medicine and is the first choice for treating the respiratory depression of opioids, also by lay-people witnessing an opioid overdose. Naloxone acts by competitive displacement of opioid agonists at the μ-opioid receptor (MOR). Its effect depends on pharmacological characteristics of the opioid agonist, such as dissociation rate from the MOR receptor and constitution of the victim. Aim of treatment is a balancing act between restoration of respiration (not consciousness) and avoidance of withdrawal, achieved by titration to response after initial doses of 0.4-2 mg. Naloxone is rapidly eliminated [half-life (t1/2) 60-120 min] due to high clearance. Metabolites are inactive. Major routes for administration are intravenous, intramuscular, and intranasal, the latter primarily for take-home naloxone. Nasal bioavailability is about 50%. Nasal uptake [mean time to maximum concentration (Tmax) 15-30 min] is likely slower than intramuscular, as reversal of respiration lag behind intramuscular naloxone in overdose victims. The intraindividual, interindividual and between-study variability in pharmacokinetics in volunteers are large. Variability in the target population is unknown. The duration of action of 1 mg intravenous (IV) is 2 h, possibly longer by intramuscular and intranasal administration. Initial parenteral doses of 0.4-0.8 mg are usually sufficient to restore breathing after heroin overdose. Fentanyl overdoses likely require higher doses of naloxone. Controlled clinical trials are feasible in opioid overdose but are absent in cohorts with synthetic opioids. Modeling studies provide valuable insight in pharmacotherapy but cannot replace clinical trials. Laypeople should always have access to at least two dose kits for their interim intervention.

High-Dose Naloxone Formulations Are Not as Essential as We Thought

Naloxone is a U.S. Food and Drug Administration (FDA) approved opioid antagonist for reversing opioid overdoses. Naloxone is available to the public, and can be administered through intramuscular (IM), intravenous (IV), and intranasal spray (IN) routes. Our literature review aimed to improve understanding regarding the adequacy of the regularly distributed two doses of low-dose IM or IN naloxone in effectively reversing fentanyl overdoses and whether high-dose naloxone formulations (HDNF) formulations are an optimal solution to this problem. Moreover, our initiative incorporated the perspectives and experiences of people who use drugs (PWUD), enabling a more practical and contextually-grounded analysis. We began by discussing the knowledge and perspectives of Tennessee Harm Reduction, a small peer-led harm reduction organization. A comprehensive literature review was then conducted to gather relevant scholarly works on the subject matter. The evidence indicates that, although higher doses of naloxone have been administered in both clinical and community settings, the vast majority of fentanyl overdoses can be successfully reversed using standard IM dosages with the exception of carfentanil overdoses and other more potent fentanyl analogs, which necessitate three or more doses for effective reversal. Multiple studies documented the risk of precipitated withdrawal using high doses of naloxone. Notably, the possibility of recurring overdose symptoms after resuscitation exists, contingent upon the half-life of the specific opioid. Considering these findings and the current community practice of distributing multiple doses, we recommend providing at least four standard doses of IN or IM naloxone to each potential bystander, and training them to continue administration until the recipient achieves stability, ensuring appropriate intervals between each dose. Based on the evidence, we do not recommend HDNF in the place of providing four doses of standard naloxone due to the higher cost, risk of precipitated withdrawal and limited evidence compared to standard IN and IM. All results must be taken into consideration with the inclusion of the lived experiences, individual requirements, and consent of PWUD as crucial factors. It is imperative to refrain from formulating decisions concerning PWUD in their absence, as their participation and voices should be integral to the decision-making process.

"Another tool in the toolkit"-Perceptions, suggestions, and concerns of emergency service providers about the implementation of a supervised consumption site

BACKGROUND

As Supervised Consumption Sites (SCS) are implemented in the United States, it is important to consider the needs and perceptions of impacted stakeholders. Emergency service providers (ESP) have a central role in responding to the overdose epidemic. This study intended to assess the how ESP perceive the potential implementation of an SCS in their community, as well as solicit program design and implementation-related concerns and suggestions.

METHODS

In-depth interviews were conducted by videoconference with 22 ESP, including firefighters, paramedics, police, and social workers in King County, Washington, USA. Data were analyzed using a thematic analysis approach.

RESULTS

Participants expressed the importance of feeling safe while responding to calls where drug use is involved and highlighted how this perception would be linked to ESP response times to calls from an SCS. Suggestions for improving the perceived safety of an SCS included training program staff in de-escalation as well as planning the layout of the SCS to accommodate ESP. The inadequacy of the emergency department as a point of care for PWUD was also identified as a theme, and some participants expressed enthusiasm regarding the prospect of the SCS as an alternative destination for transport. Finally, support for the SCS model was conditional on the appropriate utilization of emergency services and a reduction in call volume. Participants listed clarifying roles and pursuing opportunities for collaboration as ways to ensure appropriate utilization and maintain positive working relationships.

CONCLUSION

This study builds on literature regarding stakeholder perceptions of SCS by focusing on the perceptions of a critically important stakeholder group. Results enhance understanding of what motivates ESP to support SCS implementation in their community. Other novel insights pertain to ESP thoughts about alternative care delivery models and strategies for emergency department visit diversion.

Pharmacokinetic considerations for community-based dosing of nasal naloxone in opioid overdose in adults

INTRODUCTION

The administration of the opioid antagonist naloxone in the community is a measure to prevent death from opioid overdose. Approved nasal naloxone sprays deliver initial doses of 0.9 to 8 mg. The level of the initial community dose is controversial, as the scientific base is weak.In this review knowledge of the pharmacokinetics of nasal, both approved and improvised nasal sprays, and intramuscular naloxone will be utilized to evaluate dose-effect relationships in previous studies of opioid overdose outcomes.

AREAS COVERED

The aim was to present scientifically based considerations on the initial nasal naloxone doses currently available, which reasonably balances the effect and adverse outcomes, given that at least two doses are at hand. Also included in these considerations is the challenge by illicitly manufactured fentanyl and analogs.This paper is based on both peer-reviewed and grey literature identified by several searches, of such as naloxone pharmacokinetics/formulations/outcomes/emergency medical services, in PubMed and Embase.

EXPERT OPINION

There is little scientific evidence that supports the use of initial systemic dosing that exceeds 0.8 mg in the community. Higher doses increase the risk of withdrawal symptoms feared in people who use opioids. Many obstacles may reduce the potential of community-administered naloxone.

The need for multiple naloxone administrations for opioid overdose reversals: A review of the literature

Background A growing challenge in the opioid epidemic is the rise of highly potent synthetic opioids, (i.e., illicitly manufactured fentanyl [IMF]) entering the US non-prescription opioid market. Successful reversal may require multiple doses of naloxone, the standard of care for opioid overdose. We conducted a narrative literature review to summarize the rates of multiple naloxone administrations (MNA) for opioid overdose reversal. Methods: A MEDLINE search was conducted for published articles using MESH search terms: opioid overdose, naloxone and multiple naloxone administration. Of the 2,101 studies identified, articles meeting inclusion/exclusion criteria were reviewed, categorized by primary and secondary outcomes of interest and summarized by data source and study design. Results: A total of 24 articles meeting eligibility criteria were included. Among EMS-based studies, MNA rates ranged from 9% to 53%; in general, bystander-reported studies were notably higher, from 16% to 89%. Variation in study design, data sources, year and geography, may have contributed to these ranges. Three studies that included longitudinal results reported a significant percent increase between 26% and 43% in annual MNA rates or a significant increase in mean naloxone doses over time (p < .001). Conclusions: This summary found that multiple naloxone administrations during opioid overdose encounters vary widely, have occurred in up to 89% of all opioid overdoses, and have significantly increased over time. Higher naloxone formulations may fulfill an unmet need in opioid overdose reversals, given the rising rates of overdoses involving IMF. Further studies are needed to gain a better understanding of MNA during opioid overdose encounters, particularly across a wider geographic region in the US in order to inform continuing efforts to combat the opioid epidemic.

Treatment of opioid overdose: current approaches and recent advances

BACKGROUND

The USA has recently entered the third decade of the opioid epidemic. Opioid overdose deaths reached a new record of over 74,000 in a 12-month period ending April 2021. Naloxone is the primary opioid overdose reversal agent, but concern has been raised that naloxone is not efficacious against the pervasive illicit high potency opioids (i.e., fentanyl and fentanyl analogs).

METHODS

This narrative review provides a brief overview of naloxone, including its history and pharmacology, and the evidence regarding naloxone efficacy against fentanyl and fentanyl analogs. We also highlight current advances in overdose treatments and technologies that have been tested in humans.

RESULTS AND CONCLUSIONS

The argument that naloxone is not efficacious against fentanyl and fentanyl analogs rests on case studies, retrospective analyses of community outbreaks, pharmacokinetics, and pharmacodynamics. No well-controlled studies have been conducted to test this argument, and the current literature provides limited evidence to suggest that naloxone is ineffective against fentanyl or fentanyl analog overdose. Rather a central concern for treating fentanyl/fentanyl analog overdose is the rapidity of overdose onset and the narrow window for treatment. It is also difficult to determine if other non-opioid substances are contributing to a drug overdose, for which naloxone is not an effective treatment. Alternative pharmacological approaches that are currently being studied in humans include other opioid receptor antagonists (e.g., nalmefene), respiratory stimulants, and buprenorphine. None of these approaches target polysubstance overdose and only one novel approach (a wearable naloxone delivery device) would address the narrow treatment window.

Take-Home Naloxone Kits: Attitudes and Likelihood-Of-Use Outcomes from a European Survey of Potential Overdose Witnesses

BACKGROUND

Injectable naloxone is already provided as take-home naloxone (THN), and new concentrated intranasal naloxone is now being introduced in Europe. Despite evidence of the effectiveness and cost-effectiveness of THN, little is known about the attitudes of key target populations: people who use opioids (PWUO), family/friends, and staff. We examined the acceptability of different naloxone devices (ampoule, prefilled syringe, and concentrated nasal spray) across 5 European countries.

OBJECTIVES

The aim of this study was to compare THN target groups (PWUO vs. family/friends vs. staff) in their past rates of witnessed overdose and THN administration (as indicators of future use), current THN device preference, and THN carriage on the day of survey.

METHOD

Cross-sectional survey of respondents (age ≥18) in addiction treatment, harm reduction, and recovery services in Denmark, England, Estonia, Norway, and Scotland. A purpose-developed questionnaire (59 items) was administered in the local language electronically or in a pen-and-paper format.

RESULTS

Among n = 725 participants, 458 were PWUO (63.2%), 214 staff (29.5%), and 53 (7.3%) family members. The groups differed significantly in their likelihood-of-future THN use (p < 0.001): PWUO had the highest rate of previously witnessing overdoses (352; 77.7%), and staff members reported the highest past naloxone use (62; 30.1%). Across all groups, most respondents (503; 72.4%) perceived the nasal spray device to be the easiest to use. Most reported willingness to use the spray in an overdose emergency (508; 73.5%), followed by the prefilled syringe (457; 66.2%) and ampoules (64; 38.2%). Average THN carriage was 18.6%, ranging from 17.4% (PWUO) to 29.6% (family members).

CONCLUSION

Respondents considered the concentrated naloxone nasal spray the easiest device to use. Still, most expressed willingness to use the nasal spray as well as the prefilled syringe in an overdose emergency. Carriage rates were generally low, with fewer than 1 in 5 respondents carrying their THN kit on the day of the survey.

A Study on the Efficacy of a Naloxone Training Program

Introduction: The use of naloxone to reverse a potentially fatal opioid overdose is a harm reduction strategy that reduces mortality and increases the potential for referral to substance use treatment for affected individuals. In the setting of outreach performed by a street medicine team, we aimed to determine the effectiveness of an educational intervention involving distribution of naloxone accompanied by a brief instructive session about opioids, opioid overdose, and medication administration.

Methods: Our street medicine outreach team distributed 200 naloxone kits to clinicians and volunteers involved in caring for patients on ‘street rounds,’ as well as in shelters, soup kitchens, and street medicine clinic settings. Those receiving a naloxone kit engaged in a peer-reviewed presentation on how to safely use the medication to reverse a potentially fatal opioid overdose. The study team developed and administered a pre- and post-survey of 10 multiple choice questions on material covered in the educational training. The pre- and post-survey scores were compared to assess the effectiveness of implementing this training. Results were stratified by participant gender and age group.

Results: Out of the 200 participants, six were excluded from the analysis due to completely missing data from one or both surveys. The mean age of participants was 40.2±12.5 years; 120 (65.6%) were female, 62 (33.9%) were male, and 1 (0.6%) identified as nonbinary. Every survey question had an increase in correct responses from pre-survey to post-survey (identified by an increase in the percentage of correct responses). The mean survey total score increased from 5.5±1.6 to 7.5±1.3. Within the sample of 194, the mean difference in scores from pre-survey to post-survey was 2.02 points (95% CI [1.77, 2.26]), p<0.0001. Males had a mean increase in the total score from 5.6±1.8 to 7.4±1.1. Females had a mean increase in the total score from 5.5±1.5 to 7.5±1.3. The difference in total scores in males was 1.89 points (95% CI [1.42, 2.35]), p<0.0001, and in females was 2.02 points (95% CI [1.71, 2.32]), p<0.0001. Post-test scores improved in all age groups.

Conclusion: The educational training on opioids, opioid overdose, and the use of naloxone was an effective adjunct to naloxone kit distribution to volunteers and clinicians caring for people experiencing homelessness.

The Public Health Approach to the Worsening Opioid Crisis in the United States Calls for Harm Reduction Strategies to Mitigate the Harm From Opioid Addiction and Overdose Deaths

The opioid crisis has devastated the U.S. more than any other country, and the epidemic is getting worse. While opioid prescriptions have decreased by more than 40% from its peak in 2010, unfortunately, opioid-related overdose deaths have not declined but continued to increase. With greater scrutiny on prescription opioids, many users switched to the cheaper and more readily available heroin that drove up heroin-related overdose deaths from 2010 to peak in 2016, being overtaken by the spike in synthetic opioid (mostly fentanyl)-related overdose deaths. The surge in fentanyl-related overdose deaths since 2013 is alarming as fentanyl is more potent and deadly. One thing is certain the opioid crisis is not improving but has become dire with the surge in fentanyl-related overdose deaths. Evidence-based strategies have to be implemented in the U.S. to control this epidemic before it destroys more lives. Other countries, including European countries and Canada, have invested more in harm reduction strategies than the U.S. even though they (especially Europe) do not face anywhere near the level of crisis as the U.S. In the long-run, upstream measures (tackling the social determinants of health) are more effective public health strategies to control the epidemic. In the meantime, however, harm reduction strategies have to be employed to mitigate the harm from addiction and overdose deaths.

Treatment of overdose in the synthetic opioid era

Overdose deaths are often viewed as the leading edge of the opioid epidemic which has gripped the United States over the past two decades (Skolnick, 2018a). This emphasis is perhaps unsurprising because opioid overdose is both the number-one cause of death for individuals between 25 and 64 years old (Dezfulian et al., 2021) and a significant contributor to the decline in average lifespan (Dowell et al., 2017). Exacerbated by the COVID 19 pandemic, it was estimated there were 93,400 drug overdose deaths in the United States during the 12 months ending December 2020, with more than 69,000 (that is, >74%) of these fatalities attributed to opioid overdose (Ahmad et al., 2021). However, the focus on mortality statistics (Ahmad et al., 2021; Shover et al., 2020) tends to obscure the broader medical impact of nonfatal opioid overdose. Analyses of multiple databases indicate that for each opioid-induced fatality, there are between 6.4 and 8.4 non-fatal overdoses, exacting a significant burden on both the individual and society. Over the past 7-8 years, there has been an alarming increase in the misuse of synthetic opioids ("synthetics"), primarily fentanyl and related piperidine-based analogs. Within the past 2-3 years, a structurally unrelated class of high potency synthetics, benzimidazoles exemplified by etonitazene and isotonitazene ("iso"), have also appeared in illicit drug markets (Thompson, 2020; Ujvary et al. 2021). In 2020, it was estimated that over 80% of fatal opioid overdoses in the United States now involve synthetics (Ahmad et al., 2021). The unique physicochemical and pharmacological properties of synthetics described in this review are responsible for both the morbidity and mortality associated with their misuse as well as their widespread availability. This dramatic increase in the misuse of synthetics is often referred to as the "3rd wave" (Pardo et al., 2019; Volkow and Blanco, 2020) of the opioid epidemic. Among the consequences resulting from misuse of these potent opioids is the need for higher doses of the competitive antagonist, naloxone, to reverse an overdose. The development of more effective reversal agents such as those described in this review is an essential component of a tripartite strategy (Volkow and Collins, 2017) to reduce the biopsychosocial impact of opioid misuse in the "synthetic era".

Willingness to use a wearable device capable of detecting and reversing overdose among people who use opioids in Philadelphia

Background

The incidence of opioid-related overdose deaths has been rising for 30 years and has been further exacerbated amidst the COVID-19 pandemic. Naloxone can reverse opioid overdose, lower death rates, and enable a transition to medication for opioid use disorder. Though current formulations for community use of naloxone have been shown to be safe and effective public health interventions, they rely on bystander presence. We sought to understand the preferences and minimum necessary conditions for wearing a device capable of sensing and reversing opioid overdose among people who regularly use opioids.

Methods

We conducted a combined cross-sectional survey and semi-structured interview at a respite center, shelter, and syringe exchange drop-in program in Philadelphia, Pennsylvania, USA, during the COVID-19 pandemic in August and September 2020. The primary aim was to explore the proportion of participants who would use a wearable device to detect and reverse overdose. Preferences regarding designs and functionalities were collected via a questionnaire with items having Likert-based response options and a semi-structured interview intended to elicit feedback on prototype designs. Independent variables included demographics, opioid use habits, and previous experience with overdose.

Results

A total of 97 adults with an opioid use history of at least 3 months were interviewed. A majority of survey participants (76%) reported a willingness to use a device capable of detecting an overdose and automatically administering a reversal agent upon initial survey. When reflecting on the prototype, most respondents (75.5%) reported that they would wear the device always or most of the time. Respondents indicated discreetness and comfort as important factors that increased their chance of uptake. Respondents suggested that people experiencing homelessness and those with low tolerance for opioids would be in greatest need of the device.

Conclusions

The majority of people sampled with a history of opioid use in an urban setting were interested in having access to a device capable of detecting and reversing an opioid overdose. Participants emphasized privacy and comfort as the most important factors influencing their willingness to use such a device.

Trial registration

NCT04530591.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12954-021-00522-3.

Methocinnamox Reverses and Prevents Fentanyl-Induced Ventilatory Depression in Rats

Opioid use disorder affects over 2 million Americans with an increasing number of deaths due to overdose from the synthetic opioid fentanyl and its analogs. The Food and Drug Administration-approved opioid receptor antagonist naloxone (e.g., Narcan) is used currently to treat overdose; however, a short duration of action limits its clinical utility. Methocinnamox (MCAM) is a long-lasting opioid receptor antagonist that may reverse and prevent the ventilatory-depressant effects of fentanyl. This study compared the ability of naloxone (0.0001-10 mg/kg) and MCAM (0.0001-10 mg/kg) to reverse and prevent ventilatory depression by fentanyl and compared the duration of action of MCAM intravenously and subcutaneously in two procedures: ventilation and warm-water tail withdrawal. In male Sprague-Dawley rats (N = 8), fentanyl (0.0032-0.178 mg/kg, i.v.) decreased minute volume in a dose- and time-dependent manner with a dose of 0.178 mg/kg decreasing V_E to less than 40% of control. MCAM and naloxone reversed the ventilatory-depressant effects of 0.178 mg/kg fentanyl in a dose-related manner. The day after antagonist administration, MCAM but not naloxone attenuated the ventilatory-depressant effects of fentanyl. The duration of action of MCAM lasted up to 3 days and at least 2 weeks after intravenous and subcutaneous administration, respectively. MCAM attenuated the antinociceptive effects of fentanyl, with antagonism lasting up to 5 days and more than 2 weeks after intravenous and subcutaneous administration, respectively. Reversal and prolonged antagonism by MCAM might provide an effective treatment option for the opioid crisis, particularly toxicity from fentanyl and related highly potent analogs. SIGNIFICANCE STATEMENT: This study demonstrates that like naloxone, methocinnamox (MCAM) reverses the ventilatory-depressant effects of fentanyl in a time- and dose-related manner. However, unlike naloxone, the duration of action of MCAM was greater than 2 weeks when administered subcutaneously and up to 5 days when administered intravenously. These data suggest that MCAM might be particularly useful for rescuing individuals from opioid overdose, including fentanyl overdose, as well as protecting against the reemergence of ventilatory depression (renarconization).

A qualitative study of repeat naloxone administrations during opioid overdose intervention by people who use opioids in New York City

BACKGROUND

Take-home naloxone (THN) kits have been designed to provide community members (including people who use drugs, their families and/or significant others) with the necessary resources to address out-of-hospital opioid overdose events. Kits typically include two doses of naloxone. This 'twin-pack' format means that lay responders need information on how to use each dose. Advice given tends to be based on dosage algorithms used by medical personnel. However, little is currently known about how and why people who use drugs, acting as lay responders, decide to administer the second dose contained within single THN kits. The aim of this article is to explore this issue.

METHODS

Data were generated from a qualitative semi-structured interview study that was embedded within a randomised controlled trial examining the risks and benefits of Overdose Education and Naloxone Distribution (OEND) training in New York City (NYC). Analysis for this article focuses upon the experiences of 22 people who use(d) opioids and who provided repeat naloxone administrations (RNA) during 24 separate overdose events. The framework method of analysis was used to compare the time participants believed had passed between each naloxone dose administered ('subjective response interval') with the 'recommended response interval' (2-4 minutes) given during OEND training. Framework analysis also charted the various reasons and rationale for providing RNA during overdose interventions.

RESULTS

When participants' subjective response intervals were compared with the recommended response interval for naloxone dosing, three different time periods were reported for the 24 overdose events: i. 'two doses administered in under 2 minutes' (n = 10); ii. 'two doses administered within 2-4 minutes' (n = 7), and iii. 'two doses administered more than 4 minutes apart' (n = 7). A variety of reasons were identified for providing RNA within each of the three categories of response interval. Collectively, reasons for RNA included panic, recognition of urgency, delays in retrieving naloxone kit, perceptions of recipients' responsiveness/non-responsiveness to naloxone, and avoidance of Emergency Response Teams (ERT).

CONCLUSION

Findings suggest that decision-making processes by people who use opioids regarding how and when to provide RNA are influenced by factors that relate to the emergency event. In addition, the majority of RNA (17/24) occurred outside of the recommended response interval taught during OEND training. These findings are discussed in terms of evidence-based intervention and 'evidence-making intervention' with suggestions for how RNA guidance may be developed and included within future/existing models of OEND training.

Opioid overdose reversals using naloxone in New York City by people who use opioids: Implications for public health and overdose harm reduction approaches from a qualitative study

BACKGROUND

Adverse reactions to naloxone, such as withdrawal symptoms and aggression, are widely recognised in the literature by pharmaceutical manufacturers and clinical practitioners as standard reactions of individuals who are physically dependent upon opioid drugs following the reversal of potentially fatal opioid overdose. This paper seeks to provide a differentiated view on reactions to naloxone that may have important implications for public health and harm reduction approaches.

METHODS

Analyses from a qualitative investigation embedded within a 5-year Randomised Controlled Trial (RCT) examined the risks and benefits of Overdose Education and Naloxone Distribution (OEND) training models (brief or extended training) in various populations of people who use opioids in New York City. The qualitative experiences (obtained through semi-structured interviews) of 46 people who use opioids and who were each involved in the delivery of naloxone, during 56 separate overdose events that occurred throughout 2016-2018, were studied. Situational analysis and inductive content analysis of interview data focused upon overdose reversals in an attempt to provide understandings of the various adverse effects associated with naloxone from their perspective. These analyses were supplemented by data sessions within the research team during which the findings obtained from situational analysis and inductive content analysis were reviewed and complemented by deductive (clinical) appraisals of the various physical and psychological effects associated with the overdose reversals.

RESULTS

People who use opioids recognise three distinct and interconnected outcomes that may follow a successful opioid overdose reversal after intramuscular or intranasal administration of naloxone. These outcomes are here termed, (i) 'rage' (describing a wide range of angry, hostile and/or aggressive outbursts), (ii) 'withdrawal symptoms,' and (iii) 'not rage, not withdrawal' (i.e., a wide range of short-lived, 'harmless' conditions (such as temporary amnesia, mild emotional outbursts, or physical discomfort) that do not include rage or withdrawal symptoms).

CONCLUSION

Physical and psychological reactions to naloxone should not be understood exclusively as a consequence of acute, opioid-related, withdrawal symptoms. The three distinct and interconnected reversal outcomes identified in this study are considered from a harm reduction policy perspective and are further framed by concepts associated with 'mediated toxicity' (i.e., harm triggered by medicine). The overall conclusion is that harm reduction training programmes that are aligned to the policy and practice of take home naloxone may be strengthened by including awareness and training in how to best respond to 'rage' associated with overdose reversal following naloxone administration by people who use opioids and other laypersons.

Naloxone perspectives from people who use opioids: Findings from an ethnographic study in three states

BACKGROUND

Naloxone is an opioid antagonist that can reverse an opioid overdose. Increased opioid-related mortality rates led to greater distribution of naloxone without a prescription and administration of naloxone by laypersons. This study fills a gap in knowledge of naloxone experiences among active users of opioids living in suburban communities.

PURPOSE

The purpose of this article is to provide nurse practitioners with an in-depth understanding of current naloxone use practices among people who experience overdose events. The specific aims are to compare access to naloxone in diverse suburban towns, to examine administration differences across settings, and to understand perspectives on naloxone experiences from people who are actively using opioids.

METHODOLOGICAL ORIENTATION

The data for this analysis were drawn from an ethnographic study in the suburban towns around Atlanta, Georgia; Boston, Massachusetts; and New Haven, Connecticut. Short surveys and in-depth interviews were collected. Inductive methods were used to compare data across settings.

SAMPLE

The sample of 106 included 48% female, 62% White, 24% African American/Black, 13% more than one race, and 21% Hispanic/Latinx. The mean age was 41.35 years.

CONCLUSIONS

Differences between study settings in access to naloxone, administration frequency, and delivery systems were found. Findings suggest more education and training is needed in overdose prevention and harm reduction intervention. Studies on delivery systems need to address the increase in fentanyl-related overdoses.

IMPLICATIONS FOR PRACTICE

Nurse practitioners can help to target distribution of naloxone in local communities, facilitate collaboration with harm reduction services, and provide evidence-based education and training to laypersons.

A descriptive study of racial and ethnic differences of drug overdoses and naloxone administration in Pennsylvania

INTRODUCTION

Drug overdose is a significant public health problem, yet little is known about racial/ethnic differences in drug overdose rates and/or in responses to a drug overdose following naloxone administration. This paper examines differences in rates of survivorship, response, revival and administration of naloxone by race and ethnicity among those who experienced a drug overdose in Pennsylvania between January 1, 2018 and December 31, 2019. Spatio-temporal variations in drug overdose locations were examined to facilitate understanding of service development, planning, and delivery of effective treatment need.

METHODS

Ten thousand two hundred and ninety drug overdose incidents were analyzed from the Pennsylvania Overdose Information Network (ODIN). The ODIN is a centralized repository that contains information on drug overdoses victims including age, gender and race/ethnicity, naloxone administrations and survivorship, drug(s) suspected of causing the overdose, victim outcomes (e.g. hospitalizations and arrests) and average naloxone dosage per victim. Between group differences were tested using χ2 -tests of independence. Multivariate logistic regression was used to estimate the predicted probability of survivorship according to victim characteristics. All statistical analyses and mapping were performed using the R statistical programming environment.

RESULTS

About eighty-seven percent of drug overdose response victims were white, and seventy-one percent were between the ages of 20-39. White females were more likely to receive an overdose response compared to black or Hispanic females. A non-opioid was indicated more frequently in overdoses involving black victims compared to either whites or Latinos. Latinos and blacks were more likely to survive a drug overdose. However, following naloxone administration, no racial or ethnic differences in survivorship were noted. Differences in responsiveness to naloxone and transitions to care following the drug overdose event were also found. Finally, overdoses among Blacks and Latinos demonstrated a stronger spatial patterning across counties compared to whites.

CONCLUSIONS

This study found a significant, disparate impact of race/ethnicity on fatal drug overdoses when naloxone is not administered. Further, individuals who were administered naloxone and subsequently received medical care in a hospital experienced lower drug-related mortality, suggesting that first responders are critical intervention points for individuals in need of medical treatment following a drug overdose. However, while naloxone administration is a necessary first step in the recovery process, longitudinal pathways towards treatment are critical to stem the drug overdose crisis.

Take-Home Naloxone for the Emergency Interim Management of Opioid Overdose: The Public Health Application of an Emergency Medicine

Naloxone is a well-established essential medicine for the treatment of life-threatening heroin/opioid overdose in emergency medicine. Over two decades, the concept of 'take-home naloxone' has evolved, comprising pre-provision of an emergency supply to laypersons likely to witness an opioid overdose (e.g. peers and family members of people who use opioids as well as non-medical personnel), with the recommendation to administer the naloxone to the overdose victim as interim care while awaiting an ambulance. There is an urgent need for more widespread naloxone access considering the growing problem of opioid overdose deaths, accounting for more than 100,000 deaths worldwide annually. Rises in mortality are particularly sharp in North America, where the ongoing prescription opioid problem is now overlaid with a rapid growth in overdose deaths from heroin and illicit fentanyl. Using opioids alone is dangerous, and the mortality risk is clustered at certain times and contexts, including on prison release and discharge from hospital and residential care. The provision of take-home naloxone has required the introduction of new legislation and new naloxone products. These include pre-filled syringes and auto-injectors and, crucially, new concentrated nasal sprays (four formulations recently approved in different countries) with speed of onset comparable to intramuscular naloxone and relative bioavailability of approximately 40-50%. Choosing the right naloxone dose in the fentanyl era is a matter of ongoing debate, but the safety margin of the approved nasal sprays is superior to improvised nasal kits. New legislation in different countries permits over-the-counter sales or other prescription-free methods of provision. However, access remains uneven with take-home naloxone still not provided in many countries and communities, and with ongoing barriers contributing to implementation inertia. Take-home naloxone is an important component of the response to the global overdose problem, but greater commitment to implementation will be essential, alongside improved affordable products, if a greater impact is to be achieved.

Behavioral Pharmacology of Drugs Acting at Mu Opioid Receptors

Despite the therapeutic utility of opioids for relieving pain, other behavioral effects, including their potential for abuse and overdose, can be quite detrimental to individuals as well as society and have contributed to the ongoing opioid crisis. The dramatic escalation in overdose deaths over the last 15 years was initially driven by abuse of prescription opioids, although abuse of heroin, fentanyl, and fentanyl analogs has been increasing, largely due to increased availability and lower cost compared with prescription opioids. All of these opioids share pharmacological properties, acting as agonists at mu opioid receptors, and produce similar behavioral effects, including abuse-related, pain-relieving, dependence-producing, and respiratory-depressant effects. Despite their similarities, opioids are not pharmacologically identical. In fact, drugs that act at mu opioid receptors, including abused opioids, can vary on a number of dimensions, including pharmacological efficacy, drug-receptor interactions, receptor selectivity, and pharmacokinetics. Overall, these differences impact behavioral effects of drugs acting at mu opioid receptors, and this chapter describes variations in those behavioral effects and how these differences continue to provide new strategies that can be developed to address the ongoing opioid epidemic.

Intranasal naloxone rapidly occupies brain mu-opioid receptors in human subjects

Nasal spray formulations of naloxone, a mu-opioid receptor (MOR) antagonist, are currently used for the treatment of opioid overdose. They may have additional therapeutic utility also in the absence of opioid agonist drugs, but the onset and duration of action at brain MORs have been inadequately characterized to allow such projections. This study provides initial characterization of brain MOR availability at high temporal resolution following intranasal (IN) naloxone administration to healthy volunteers in the absence of a competing opioid agonist. Fourteen participants were scanned twice using positron emission tomography (PET) and [¹¹C]carfentanil, a selective MOR agonist radioligand. Concentrations of naloxone in plasma and MOR availability (relative to placebo) were monitored from 0 to 60 min and at 300-360 min post naloxone. Naloxone plasma concentrations peaked at ~20 min post naloxone, associated with slightly delayed development of brain MOR occupancy (half of peak occupancy reached at ~10 min). Estimated peak occupancies were 67 and 85% following 2 and 4 mg IN doses, respectively. The estimated half-life of occupancy disappearance was ~100 min. The rapid onset of brain MOR occupancy by IN naloxone, evidenced by the rapid onset of its action in opioid overdose victims, was directly documented in humans for the first time. The employed high temporal-resolution PET method establishes a model that can be used to predict brain MOR occupancy from plasma naloxone concentrations. IN naloxone may have therapeutic utility in various addictions where brain opioid receptors are implicated, such as gambling disorder and alcohol use disorder.

Fighting Fire with Fire: Development of Intranasal Nalmefene to Treat Synthetic Opioid Overdose

The dramatic rise in overdose deaths linked to synthetic opioids (e.g., fentanyl, carfentanil) may require more potent, longer-duration opiate antagonists than naloxone. Both the high affinity of nalmefene at μ opiate receptors and its long half-life led us to examine the feasibility of developing an intranasal (IN) formulation as a rescue medication that could be especially useful in treating synthetic opioid overdose. In this study, the pharmacokinetic properties of IN nalmefene were compared with an intramuscular (i.m.) injection in a cohort of healthy volunteers. Nalmefene was absorbed slowly following IN administration, with a median time to reach C_max (T_max) of 2 hours. Addition of the absorption enhancer dodecyl maltoside (Intravail, Neurelis, Inc., Encinitas, CA) reduced T_max to 0.25 hour and increased C_max by ∼2.2-fold. The pharmacokinetic properties of IN nalmefene (3 mg) formulated with dodecyl maltoside has characteristics consistent with an effective rescue medication: its onset of action is comparable to an i.m. injection of nalmefene (1.5 mg) previously approved to treat opioid overdose. Furthermore, the C_max following IN administration was ∼3-fold higher than following i.m. dosing, comparable to previously reported plasma concentrations of nalmefene observed 5 minutes following a 1-mg i.v. dose. The high affinity, very rapid onset, and long half-life (>7 hours) of IN nalmefene present distinct advantages as a rescue medication, particularly against longer-lived synthetic opioids.

Reversal and Prevention of the Respiratory-Depressant Effects of Heroin by the Novel μ-Opioid Receptor Antagonist Methocinnamox in Rhesus Monkeys

One consequence of the ongoing opioid epidemic is a large number of overdose deaths. Naloxone reverses opioid-induced respiratory depression; however, its short duration of action limits the protection it can provide. Methocinnamox (MCAM) is a novel opioid receptor antagonist with a long duration of action. This study examined the ability of MCAM to prevent and reverse the respiratory-depressant effects (minute volume [V_E]) of heroin in five monkeys. MCAM (0.32 mg/kg) was given before heroin to determine whether it prevents respiratory depression; heroin dose-effect curves were generated 1, 2, 4, and 8 days later, and these effects were compared with those of naltrexone (0.032 mg/kg). Heroin dose dependently decreased V_E MCAM and naltrexone prevented respiratory depression, shifting the heroin dose-effect curve rightward at least 10-fold. MCAM, but not naltrexone, attenuated these effects of heroin for 4 days. MCAM (0.1-0.32 mg/kg) was given 30 minutes after heroin to determine whether it reverses respiratory depression; heroin dose-effect curves were generated 1, 2, 4, 8, and 16 days later, and these effects were compared with those of naloxone (0.0032-0.1 mg/kg). MCAM and naloxone reversed respiratory depression within 30 minutes, although only MCAM antagonized heroin on subsequent days. Thus, MCAM prevents and reverses respiratory depression, the potentially lethal effect of heroin, longer than opioid receptor antagonists currently in use. Because of its sustained effects, MCAM might provide more effective rescue from and protection against the fatal respiratory-depressant effects of opioids, thereby improving treatment of opioid overdose.

[Interest of take-home naloxone for opioid overdose]

Over the course of these last decades, we observed a change on opioid use with the marketing of opiate maintenance treatment, an increase of opioids used for pain management and recent concerns have arisen around the use of synthetic opioid. The World Health Organization (WHO) reports around 70,000 people opioid overdose death each year. In France, according to the DRAMES program (fatalities in relation with abuse of licit or illicit drugs) of the French addictovigilance network, most of deaths are related to opioids overdose (especially methadone, following by heroin, buprenorphine and opioid used for pain management). Opioid overdose is treatable with naloxone, an opioid antagonist which rapidly reverses the effects of opioids. In recent years, a number of programs around the world have shown that it is feasible to provide naloxone to people likely to witness an opioid overdose. In 2014, the WHO published recommendations for this provision and the need to train users and their entourage in the management of opioid overdose. In this context, in July 2016, French drug agency has granted a temporary authorization for use of a naloxone nasal spray Nalscue^®. Because different opioids can be used and because each opioid has specific characteristics (pharmacodynamics, pharmacokinetics, galenic form…), the risk of overdose may differ from one opioid to another and it may be necessary, depending on the clinical context, to use larger and repeated doses of naloxone.

Pharmacokinetic properties of intranasal and injectable formulations of naloxone for community use: a systematic review

Aim: To assess the pharmacokinetic properties of community-use formulations of naloxone for emergency treatment of opioid overdose. Methods: Systematic literature review based on searches of established databases and congress archives. Results: Seven studies met inclusion criteria: two of US FDA-approved intramuscular (im.)/subcutaneous (sc.) auto-injectors, one of an FDA-approved intranasal spray, two of unapproved intranasal kits (syringe with atomizer attachment) and two of intranasal products in development. Conclusion: The pharmacokinetics of im./sc. auto-injector 2 mg and approved intranasal spray (2 and 4 mg) demonstrated rapid uptake and naloxone exposure exceeding that of the historic benchmark (0.4 mg im.), indicating that naloxone exposure was adequate for reversal of opioid overdose.