Buprenorphine/naloxone - one formulation that doesn't fit all: a case report.

BACKGROUND: Sublingual buprenorphine, approved for treatment of opioid use disorder since 2002, is most commonly available in co-formulation with naloxone. Naloxone is an opioid antagonist minimally absorbed when sublingual (SL) buprenorphine/naloxone is taken as prescribed; it is thought to reduce potential for misuse via intravenous administration. However, growing data and clinical experience demonstrate that previously accepted assumptions about the pharmacokinetics of these medications may not apply to all patients. CASE PRESENTATION: We present a patient whose adverse post-administration side effects on SL buprenorphine/naloxone resolved with transition to SL buprenorphine monoproduct. DISCUSSION: Naloxone can be detected in nearly all patients taking SL buprenorphine/naloxone, though with apparent variability in clinical effect. In a minority of patients, naloxone can contribute to adverse and potentially treatment-limiting side effects. Furthermore, the naloxone component is commonly misunderstood by patients and providers and can foster mistrust in the therapeutic relationship if providers are perceived to be withholding a more tolerable formulation. Prescribers should have a low threshold to offer buprenorphine alone when clinically appropriate.

Neurobehavioral outcomes of infants exposed to buprenorphine-naloxone compared with naltrexone during pregnancy.

BACKGROUND: Naltrexone is a medication used to treat both opioid and alcohol use disorder with limited experience in pregnant individuals, particularly in comparison to more commonly utilized treatments such as buprenorphine-naloxone. The long-term outcomes of infants exposed to naltrexone has not been previously examined. AIMS: To compare the neurobehavioral outcomes of naltrexone versus buprenorphine-naloxone exposed infants. STUDY DESIGN: Multi-centered prospective cohort study. SUBJECTS: Pregnant people on prescribed buprenorphine-naloxone or naltrexone were enrolled during pregnancy and the dyad followed until 12 months after delivery. OUTCOME MEASURES: Infants were evaluated at 4-6 weeks corrected gestational age (CGA) using the NICU Neonatal Neurobehavioral Scale (NNNS) and at the 12-month CGA visit using the Ages and Stages Questionnaire, Third Edition (ASQ-3). RESULTS: There were 7 dyads in the naltrexone group and 34 in the buprenorphine-naloxone group. On the NNNS, infants exposed to naltrexone had higher median scores for arousal and excitability, and lower median scores for attention and regulation at 4-6 weeks CGA compared to the buprenorphine-naloxone group. None of the infants in the naltrexone group were monitored for NOWS and had shorter length of hospital stay compared with the buprenorphine-naloxone group. Although no statistically significant differences were observed, more infants in the buprenorphine-naloxone group were identified as at risk for development delays in the communication, problem solving, and personal social domains of the ASQ-3 at 12 months CGA. Results should be interpreted with caution given this study's small sample size and lack of a prospective comparison cohort. CONCLUSIONS: In this small cohort, there are differences noted in infant neurobehavior by NNNS at 4-6 weeks of age when comparing the buprenorphine-naloxone and naltrexone groups. At 12 months, ASQ-3 scores were similar but with percentage differences in potential development delay risk observed between the two groups. Larger cohort studies are needed to determine the long-term child outcomes after naltrexone exposure in pregnancy.

Pharmacology of viable mechanism agnostic respiratory stimulants for the reversal of drug-induced respiratory depression in humans.

INTRODUCTION: Drug-induced respiratory depression is potentially fatal and can be caused by various drugs such as synthetic opioids and tranquilizers. The only class of respiratory depressants that has a specific reversal agent are opioids, such as naloxone. These reversal agents have limited utility in situations of polysubstance ingestion with agents from multiple respiratory depressant classes. Hence, there is an unmet need for drugs that stimulate breathing irrespective of the underlying cause of respiratory depression, i.e. mechanism agnostic respiratory stimulants. AREAS COVERED: In this review, we discuss agnostic respiratory stimulants, tested in humans with promising results, i.e. ampakines, drugs that act at the carotid bodies, N-methyl-D-aspartate receptor antagonist ketamine, and orexin receptor-2-agonist danavorexton, and others that demonstrated positive effects in animals but not yet in humans. EXPERT OPINION: Rapid, effective rescuing of individuals who overdosed on respiratory depressants saves lives. While naloxone is the preferred drug for reversing opioid-induced respiratory depression, its effectiveness is limited in cases involving non-opioids. While several agnostic respiratory stimulants showed promise in humans, further research is needed to optimize dosing, evaluate safety and efficacy in deeper respiratory depression (apnea). Additionally, future studies should combine agnostic stimulants with naloxone, to improve rapid, effective rescue from drug overdoses.

Systematic Review of Naloxone Dosing and Adverse Events in the Emergency Department.

BACKGROUND: Experts recommend using the lowest effective dose of naloxone to balance the reversal of opioid-induced respiratory depression and avoid precipitated opioid withdrawal, however, there is no established dosing standards within the emergency department (ED). OBJECTIVES: The aim of this review was to determine current naloxone dosing practice in the ED and their association with adverse events. METHODS: We conducted a systematic review by searching PubMed, Cochrane, Embase, and EBSCO from 2000-2021. Articles containing patient-level data for initial ED dose and patient outcome had data abstracted by two independent reviewers. Patients were divided into subgroups depending on the initial dose of i.v. naloxone: low dose ([LD], < 0.4 mg), standard dose ([SD], 0.4-2 mg), or high dose ([HD], > 2 mg). Our outcomes were the dose range administered and adverse events per dose. We compared groups using chi-squared difference of proportions or Fisher's exact test. RESULTS: The review included 13 articles with 209 patients in the results analysis: 111 patients in LD (0.04-0.1 mg), 95 in SD (0.4-2 mg), and 3 in HD (4-12 mg). At least one adverse event was reported in 37 SD patients (38.9%), compared with 14 in LD (12.6%, p < 0.0001) and 2 in HD (100.0%, p = 0.16). At least one additional dose was administered to 53 SD patients (55.8%), compared with 55 in LD (49.5%, p < 0.0001), and 3 in HD (100.0%, p = 0.48). CONCLUSIONS: Lower doses of naloxone in the ED may help reduce related adverse events without increasing the need for additional doses. Future studies should evaluate the effectiveness of lower doses of naloxone to reverse opioid-induced respiratory depression without causing precipitated opioid withdrawal.

Dental adverse effects of sublingual buprenorphine and naloxone.

Overview of: Etminan M, Rezaeianzadeh R, Kezouh A, et al. Association between sublingual buprenorphine-naloxone exposure and dental disease. JAMA. 2022;328:2269-71.

Nurse delivered medication safety screening program for home care visits.

Home care clients have safety barriers related to medication storage, disposal, and safe use of opioids. Limited research is available regarding medication safety initiatives in the home care setting. This study evaluates a medication safety initiative, linked with opioid misuse and overdose prevention screening, for home care clients with different levels of service. Training and screening tools designed for community pharmacies by the Opioid & Naloxone Education (ONE) Program were modified for use by home health nurses. All new admits to the home health services were screened for medication storage, medication disposal, and use of pain medications. Patients taking opioids were screened for opioid-specific risks. Interventions based on screening results included education, provision of medication lock boxes, drug disposal packets, and/or naloxone. Most home care clients (85%) are properly storing their medication and 38% were not properly disposing unused medications. Higher levels of care had greater pain medication needs, including the provision of naloxone. This study demonstrates the opportunity to incorporate medication safety screening into nursing home health visits.

No pain, no strain: Targin® mitigates pain and constipation following spinal cord injury.

BACKGROUND: Opioids effectively reduce chronic pain, but present significant side effects including opioid-induced constipation. Oxycodone/naloxone decreases pain and constipation in cancer patients, however its effect on spinal cord injury population remains understudied. METHODS: We assessed whether oxycodone/naloxone reduces pain, constipation, and severity of autonomic dysreflexia in an individual with spinal cord injury. A 55-year-old male with C5 lesion presented with chief complaint of chronic pain received 5/2.5 mg and 20/10 mg oxycodone/naloxone for 6 and 2 weeks, respectively. RESULTS: Oxycodone/naloxone improved pain, bowel function, and autonomic dysreflexia severity. INTERPRETATION: Oxycodone/naloxone was effective in managing chronic pain and constipation in the studied case.

Intraoperative methadone: Proceed with care.

A recent review suggests minimal respiratory depression (RD) after perioperative methadone, while another identified RD in up to 37 percent of patients. A meta-analysis is equivocal. At our institution, five of 75 opioid naive patients (6.6 percent) given perioperative methadone received naloxone. We report three of these cases in detail. Two others were discovered during an electronic medical record search for opioid naïve patients who received methadone plus naloxone during their anesthesia care. Our five patients indicate that RD owing to methadone can occur with excessive perioperative adjuvant medications and/or in patients who are taking home central nervous system depressants. We define perioperative adjuvant medications as medications given by the anesthesiologist prior to induction and intraoperatively. The risks and benefits of perioperative methadone administration, specifically in patients who received post-operative naloxone, deserve further investigation.

New-Onset Psychotic Symptoms Following Abrupt Buprenorphine/Naloxone Discontinuation in a Female Patient with Bipolar Disorder: A Case Report.

Buprenorphine and naloxone (Suboxone) is a combination medication-assisted treatment (MAT) for opioid use disorder. MAT withdrawal-induced psychosis is a rare clinical presentation. To our best knowledge, only three reports have summarized the characteristic manifestations of buprenorphine withdrawal psychosis, yet all of them were male. In this case report, we present a 41-year-old female patient with bipolar disorder and comorbid substance use disorder who developed new-onset psychosis and relapse of manic symptoms following abrupt discontinuation of Suboxone. Manic and psychotic symptoms remitted after a short-term hospitalization with the treatment of an antipsychotic and a mood stabilizer. In addition to discussing this case presentation and treatment approach, we review existing literature and discuss possible underlying mechanisms to enhance understanding of this clinical phenomenon.

Oxycodone/naloxone versus tapentadol in real-world chronic non-cancer pain management: an observational and pharmacogenetic study.

Tapentadol (TAP) and oxycodone/naloxone (OXN) potentially offer an improved opioid tolerability. However, real-world studies in chronic non-cancer pain (CNCP) remain scarce. Our aim was to compare effectiveness and security in daily pain practice, together with the influence of pharmacogenetic markers. An observational study was developed with ambulatory test cases under TAP (n = 194) or OXN (n = 175) prescription with controls (prescribed with other opioids (control), n = 216) CNCP patients. Pain intensity and relief, quality of life, morphine equivalent daily doses (MEDD), concomitant analgesic drugs, adverse events (AEs), hospital frequentation and genetic variants of OPRM1 (rs1799971, A118G) and COMT (rs4680, G472A) genes, were analysed. Test CNCP cases evidenced a significantly higher pain relief predictable due to pain intensity and quality of life (R2 = 0.3), in front of controls. Here, OXN achieved the greatest pain relief under a 28% higher MEDD, 8-13% higher use of pregabalin and duloxetine, and 23% more prescription change due to pain, compared to TAP. Whilst, TAP yielded a better tolerability due the lower number of 4 [0-6] AEs/patient, in front of OXN. Furthermore, OXN COMT-AA homozygotes evidenced higher rates of erythema and vomiting, especially in females. CNCP real-world patients achieved higher pain relief than other traditional opioids with a better tolerability for TAP. Further research is necessary to clarify the potential influence of COMT and sex on OXN side-effects.

Development of a Translational Model to Assess the Impact of Opioid Overdose and Naloxone Dosing on Respiratory Depression and Cardiac Arrest.

In response to a surge of deaths from synthetic opioid overdoses, there have been increased efforts to distribute naloxone products in community settings. Prior research has assessed the effectiveness of naloxone in the hospital setting; however, it is challenging to assess naloxone dosing regimens in the community/first-responder setting, including reversal of respiratory depression effects of fentanyl and its derivatives (fentanyls). Here, we describe the development and validation of a mechanistic model that combines opioid mu receptor binding kinetics, opioid agonist and antagonist pharmacokinetics, and human respiratory and circulatory physiology, to evaluate naloxone dosing to reverse respiratory depression. Validation supports our model, which can quantitatively predict displacement of opioids by naloxone from opioid mu receptors in vitro, hypoxia-induced cardiac arrest in vivo, and opioid-induced respiratory depression in humans from different fentanyls. After validation, overdose simulations were performed with fentanyl and carfentanil followed by administration of different intramuscular naloxone products. Carfentanil induced more cardiac arrest events and was more difficult to reverse than fentanyl. Opioid receptor binding data indicated that carfentanil has substantially slower dissociation kinetics from the opioid receptor compared with nine other fentanyls tested, which likely contributes to the difficulty in reversing carfentanil. Administration of the same dose of naloxone intramuscularly from two different naloxone products with different formulations resulted in differences in the number of virtual patients experiencing cardiac arrest. This work provides a robust framework to evaluate dosing regimens of opioid receptor antagonists to reverse opioid-induced respiratory depression, including those caused by newly emerging synthetic opioids.

Pharmacists' naloxone offering and dispensing practices.

OBJECTIVE: The primary objective of this paper is to understand pharmacists' naloxone offering and dispensing practices and factors affecting those practices. The secondary objective of this paper is to refine an existing survey instrument and use it to understand pharmacists' naloxone offering and dispensing behaviors and factors affecting it. DESIGN, SETTINGS, AND PARTICIPANTS: A statewide mail survey of pharmacists was conducted in Wisconsin using stratified random sampling. Survey data were analyzed using descriptive statistics to understand pharmacists' naloxone offering and dispensing practices and multiple regression analysis to understand factors affecting these practices. MAIN OUTCOMES: (1) Pharmacists' practices about naloxone offering and dispensing; (2) factors affecting these practices. RESULTS: Most pharmacies stocked naloxone (92.9 percent) and were under the Wisconsin standing order (80.1 percent). The majority of pharmacists reported that they occasionally (36.6 percent), rarely (29.3 percent), or never (21.5 percent) offer naloxone to patients. The majority reported that they occasionally (29.3 percent), rarely (52.4 percent), or never (15.2 percent) dispense naloxone. While most pharmacists were confident in their ability to initiate conversations about nalox-one, they were not confident on how to screen patients at risk for opioid overdose. Pharmacists offered naloxone more when they felt more confident initiating a conversation regarding the need for naloxone with patients (ß = 0.50, p < 0.05). Pharmacists dispensed naloxone more when they have had more previous training about dispensing naloxone (ß = 0.43, p < 0.05). CONCLUSION: Many pharmacists hardly offer or dispense naloxone under the standing order. Pharmacists may benefit from standardized training and resources about screening patients for risk of overdose and overdose risk communication.

Assessment of a Naloxone Coprescribing Alert for Patients at Risk of Opioid Overdose: A Quality Improvement Project.

BACKGROUND: Patients taking high doses of opioids, or taking opioids in combination with other central nervous system depressants, are at increased risk of opioid overdose. Coprescribing the opioid-reversal agent naloxone is an essential safety measure, recommended by the surgeon general, but the rate of naloxone coprescribing is low. Therefore, we set out to determine whether a targeted clinical decision support alert could increase the rate of naloxone coprescribing. METHODS: We conducted a before-after study from January 2019 to April 2021 at a large academic health system in the Southeast. We developed a targeted point of care decision support notification in the electronic health record to suggest ordering naloxone for patients who have a high risk of opioid overdose based on a high morphine equivalent daily dose (MEDD) ≥90 mg, concomitant benzodiazepine prescription, or a history of opioid use disorder or opioid overdose. We measured the rate of outpatient naloxone prescribing as our primary measure. A multivariable logistic regression model with robust variance to adjust for prescriptions within the same prescriber was implemented to estimate the association between alerts and naloxone coprescribing. RESULTS: The baseline naloxone coprescribing rate in 2019 was 0.28 (95% confidence interval [CI], 0.24-0.31) naloxone prescriptions per 100 opioid prescriptions. After alert implementation, the naloxone coprescribing rate increased to 4.51 (95% CI, 4.33-4.68) naloxone prescriptions per 100 opioid prescriptions (P < .001). The adjusted odds of naloxone coprescribing after alert implementation were approximately 28 times those during the baseline period (95% CI, 15-52). CONCLUSIONS: A targeted decision support alert for patients at risk for opioid overdose significantly increased the rate of naloxone coprescribing and was relatively easy to build.

Transition from Oxycodone to Buprenorphine/Naloxone in a Hospitalized Patient with Sickle Cell Disease: A Case Report.

Buprenorphine is increasingly used to treat pain in patients with sickle cell disease but optimal timing and approach for transitioning patients from full agonist opioids to buprenorphine is unknown. We present the case of a 22-year-old woman with sickle cell disease and acute on chronic pain who transitioned from high-dose oxycodone to buprenorphine/naloxone during a hospital stay for vaso-occlusive episode. Utilizing a microdosing approach to minimize pain and withdrawal, buprenorphine/naloxone was gradually uptitrated while she received full agonist opioids. During the transition, she experienced some withdrawal in the setting of swallowed buprenorphine/naloxone tablets, which were intended to be dosed sublingually. Nevertheless, the transition was tolerable to the patient and her pain and function significantly improved with buprenorphine treatment. This case also highlights the challenges and unique considerations that arise when providing care for the hospitalized patient who is also incarcerated.

Safety, Efficacy, and Cost of 0.4-mg Versus 2-mg Intranasal Naloxone for Treatment of Prehospital Opioid Overdose.

BACKGROUND: Intranasal naloxone is commonly used to treat prehospital opioid overdose. However, the optimal dose is unclear, and currently, no study exists comparing the clinical effect of intranasal naloxone at different doses. OBJECTIVE: The goal of this investigation was to compare the safety, efficacy, and cost of 0.4- versus 2-mg intranasal naloxone for treatment of prehospital opioid overdose. METHODS: A retrospective, cross-sectional study was performed of 218 consecutive adult patients receiving intranasal naloxone in 2 neighboring counties in Southeast Michigan: one that used a 0.4-mg protocol and one that used a 2-mg protocol. Primary outcomes were response to initial dose, requirement of additional dosing, and incidence of adverse effects. Unpooled, 2-tailed, 2-sample t-tests and χ2 tests for homogeneity were performed with statistical significance defined as P <0.05. RESULTS: There was no statistically significant difference between the 2 populations in age, mass, gender, proportion of exposures suspected as heroin, response to initial dose, required redosing, or total number of doses by any route. The overall rate of adverse effects was 2.1% under the lower-dose protocol and 29% under the higher-dose protocol (P < 0.001). The lower-dose protocol was 79% less costly. CONCLUSION AND RELEVANCE: Treatment of prehospital opioid overdose using intranasal naloxone at an initial dose of 0.4 mg was equally effective during the prehospital period as treatment at an initial dose of 2 mg, was associated with a lower rate of adverse effects, and represented a 79% reduction in cost.

The Cannabinoid Receptor Type 1 Positive Allosteric Modulator ZCZ011 Attenuates Naloxone-Precipitated Diarrhea and Weight Loss in Oxycodone-Dependent Mice.

Opioid use disorder reflects a major public health crisis of morbidity and mortality in which opioid withdrawal often contributes to continued use. However, current medications that treat opioid withdrawal symptoms are limited by their abuse liability or lack of efficacy. Although cannabinoid 1 (CB1) receptor agonists, including Δ9-tetrahydrocannabinol, ameliorate opioid withdrawal in both clinical and preclinical studies of opioid dependence, this strategy elicits cannabimimetic side effects as well as tolerance and dependence after repeated administration. Alternatively, CB1 receptor positive allosteric modulators (PAMs) enhance CB1 receptor signaling and show efficacy in rodent models of pain and cannabinoid dependence but lack cannabimimetic side effects. We hypothesize that the CB1 receptor PAM ZCZ011 attenuates naloxone-precipitated withdrawal signs in opioid-dependent mice. Accordingly, male and female mice given an escalating dosing regimen of oxycodone, a widely prescribed opioid, and challenged with naloxone displayed withdrawal signs that included diarrhea, weight loss, jumping, paw flutters, and head shakes. ZCZ011 fully attenuated naloxone-precipitated withdrawal-induced diarrhea and weight loss and reduced paw flutters by approximately half, but its effects on head shakes were unreliable, and it did not affect jumping behavior. The antidiarrheal and anti-weight loss effects of ZCZ0111 were reversed by a CB1 not a cannabinoid receptor type 2 receptor antagonist and were absent in CB1 (-/-) mice, suggesting a necessary role of CB1 receptors. Collectively, these results indicate that ZCZ011 completely blocked naloxone-precipitated diarrhea and weight loss in oxycodone-dependent mice and suggest that CB1 receptor PAMs may offer a novel strategy to treat opioid dependence. SIGNIFICANCE STATEMENT: Opioid use disorder represents a serious public health crisis in which current medications used to treat withdrawal symptoms are limited by abuse liability and side effects. The CB1 receptor positive allosteric modulator (PAM) ZCZ011, which lacks overt cannabimimetic behavioral effects, ameliorated naloxone-precipitated withdrawal signs through a CB1 receptor mechanism of action in a mouse model of oxycodone dependence. These results suggest that CB1 receptor PAMs may represent a viable strategy to treat opioid withdrawal.

Adverse events related to bystander naloxone administration in cases of suspected opioid overdose in British Columbia: An observational study.

INTRODUCTION: Take-Home Naloxone programs have been introduced across North America in response to rising opioid overdose deaths. There is currently limited real-world data on bystander naloxone administration, overdose outcomes, and evidence related to adverse events following bystander naloxone administration. METHODS: The research team used descriptive statistics from Take-Home Naloxone administration forms. We explored reported demographic variables and adverse events among people who received by-stander administered naloxone in a suspected opioid overdose event between August 31, 2012 and December 31, 2018 in British Columbia. We examined and contextualized differences across years given policy, program and drug toxicity changes. We used multivariate logistic regression to examine whether an association exists between number of ampoules of naloxone administered and the odds that the recipient will experience withdrawal symptoms. RESULTS: A large majority (98.1%) of individuals who were administered naloxone survived their overdose and 69.2% had no or only mild withdrawal symptoms. Receiving three (Adjusted Odds Ratio (AOR) 1.64 (95% Confidence Interval (CI): 1.08-2.48)) or four or more (AOR 2.19 (95% CI: 1.32-3.62)) ampoules of naloxone was significantly associated with odds of moderate or severe withdrawal compared to receiving one ampoule of naloxone. CONCLUSIONS: This study provides evidence from thousands of bystander reversed opioid overdoses using Take-Home Naloxone kits in British Columbia, and suggests bystander-administered naloxone is safe and effective for opioid overdose reversal. Data suggests an emphasis on titration during bystander naloxone training in situations where the person experiencing overdose can be adequately ventilated may help avoid severe withdrawal symptoms. We identified a decreasing trend in the likelihood of moderate or severe withdrawal over the study period.