Unmet need for medication for opioid use disorder among persons who inject drugs in 23 U.S. cities.

BACKGROUND: Persons who inject drugs (PWID) are at increased risk of HIV and hepatitis C virus (HCV) infections and premature mortality due to drug overdose. Medication for opioid use disorder (MOUD), such as methadone or buprenorphine, reduces injecting behaviors, HIV and HCV transmission, and mortality from opioid overdose. Using data from National HIV Behavioral Surveillance, we evaluated the unmet need for MOUD among PWID in 23 U.S. cities. METHODS: PWID were recruited by respondent-driven sampling, interviewed, and tested for HIV. This analysis includes PWID who were ≥18 years old and reported injecting drugs and opioid use in the past 12 months. We used Poisson regression to examine factors associated with self-reported unmet need for MOUD and reported adjusted prevalence ratios (aPR) with 95% confidence intervals. RESULTS: Of 10,879 PWID reporting using opioids, 68.8% were male, 48.2% were ≥45 years of age, 38.8% were non-Hispanic White, 49.6% experienced homelessness, and 28.0% reported an unmet need for MOUD in the past 12 months. PWID who were more likely to report unmet need for MOUD experienced homelessness (aPR 1.26; 95% CI: 1.19-1.34), were incarcerated in the past 12 months (aPR 1.15; 95% CI: 1.08-1.23), injected ≥once a day (aPR 1.42; 95% CI: 1.31-1.55), reported overdose (aPR 1.33; 95% CI: 1.24-1.42), and sharing of syringes (aPR 1.14; 95% CI: 1.06-1.23). CONCLUSIONS: The expansion of MOUD provision for PWID is critical. Integrating syringe service programs and MOUD provision and linking PWID who experience overdose, incarceration or homelessness to treatment with MOUD could improve its utilization among PWID.

Acute High-Output Heart Failure with Pulmonary Hypertension and Severe Liver Injury Caused by Amlodipine Poisoning: A Case Report.

Acute high-output heart failure (HOHF) with pulmonary hypertension and liver injury caused by amlodipine poisoning is very rare. We report a 52-year-old woman who suffered from severe shock after an overdose of amlodipine. Hemodynamic monitoring showed that while her left ventricular systolic function and cardiac output were elevated, her systemic vascular resistance decreased significantly. At the same time, the size of her right heart, her central venous pressure, and the oxygen saturation of her central venous circulation all increased abnormally. The patient's circulatory function and right ventricular dysfunction gradually improved after large doses of vasopressors and detoxification measures. However, her bilirubin and transaminase levels increased significantly on hospital day 6, with a CT scan showing patchy, low-density areas in her liver along with ascites. After liver protective treatment and plasma exchange, the patient's liver function gradually recovered. A CT scan 4 months later showed all her liver abnormalities, including ascites, had resolved. The common etiologies of HOHF were excluded in this case, and significantly reduced systemic vascular resistance caused by amlodipine overdose was thought to be the primary pathophysiological basis of HOHF. The significant increase in venous return and pulmonary blood flow is considered to be the main mechanism of right ventricular dysfunction and pulmonary hypertension. Hypoxic hepatitis caused by a combination of hepatic congestion and distributive shock may be the most important factors causing liver injury in this patient. Whether amlodipine has other mechanisms leading to HOHF and pulmonary hypertension needs to be further studied. Considering the significant increase of right heart preload, aggressive fluid resuscitation should be done very cautiously in patients with HOHF and shock secondary to amlodipine overdose.

The presence of abdominal pain associated with acetaminophen overdose does not predict severity of liver injury.

AIM: Whilst it is known that abdominal pain is a common symptom in patients with acetaminophen overdose, its association with severity of liver injury has not been clearly defined. This study investigates the association between the symptom of abdominal pain on presentation to hospital and the degree of liver injury post-acetaminophen overdose. METHODS: Admissions with acetaminophen poisoning, requiring treatment with acetylcysteine were identified and reviewed from a search of a large Australian tertiary hospital network from February 20th, 2014, to August 30th, 2018. Parameters such as presence of abdominal pain, time post-ingestion and peak ALT were collected. Single acute ingestions, staggered and repeated supratherapeutic ingestions were analysed. RESULTS: 539 cases were identified in the study period, 79% female, with mean age 25 (17-43) years. Patients presenting to the emergency department with abdominal pain post-acetaminophen overdose had a similar risk of developing hepatotoxicity or acute liver injury compared to patients without abdominal pain regardless of time to presentation. Patients presenting <8-h post-overdose with abdominal pain were as likely to develop hepatotoxicity (1/46, 2.2%) compared to those without abdominal pain (1/54 [1.9%]; OR = 1.18 [0.07 to 19.4]). Those presenting >8-h post-overdose with abdominal pain were as likely to develop hepatotoxicity (13/92, 14.1%) compared to those without abdominal pain (4/35 [11.4%]; OR = 1.28 [0.39 to 4.21]). CONCLUSIONS: The presence of abdominal pain after acetaminophen overdose was not predictive of the development of liver injury in patients receiving acetylcysteine treatment. Further prospective studies are required to confirm this finding. The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.

Successful treatment of severe calcium channel blocker poisoning, new experience with the guidance of invasive hemodynamic monitoring in a 17-year-old girl: a case report.

BACKGROUND: Calcium channel blocker poisoning is one of the most lethal cardiac drugs overdoses. Calcium and high-dose insulin infusion are the first-line therapy for symptomatic patients, and Intralipid emulsion infusion is useful for refractory cases. CASE PRESENTATION: In this report, we describe a 17-year-old Iranian girl who took 250 mg of the drug for a suicidal attempt and presented with refractory hypotension and non-cardiogenic pulmonary edema treated successfully with the guidance of invasive hemodynamic parameters. CONCLUSION: For complicated cases, in addition to supportive care and adjuvant therapy such as high-dose insulin and Intralipid, it is mandatory to utilize advanced hemodynamic monitoring to treat hypotension in severe calcium channel blocker poisoning to guide the treatment.

Providers' Experiences and Perspectives in Treating Patients With Co-Occurring Opioid and Stimulant Use Disorders in the Hospital.

BACKGROUND: The overdose crisis is increasingly characterized by opioid and stimulant co-use. Despite effective pharmacologic treatment for both opioid use disorder (OUD) and contingency management for stimulant use disorders, most individuals with these co-occurring conditions are not engaged in treatment. Hospitalization is an important opportunity to engage patients and initiate treatment, however existing hospital addiction care is not tailored for patients with co-use and may not meet the needs of this population. METHODS: Semi-structured interviews were conducted with hospital providers about their experiences and perspectives treating patients with opioid and stimulant co-use. We used directed content analysis to identify common experiences and opportunities to improve hospital-based treatment for patients with co-use. RESULTS: From qualitative interviews with 20 providers, we identified 4 themes describing how co-use complicated hospital-based substance use treatment: (1) patients' unstable circumstances impacting the treatment plan, (2) co-occurring withdrawals are difficult to identify and treat, (3) providers holding more stigmatizing views of patients with co-use, and (4) stimulant use is often "ignored" in the treatment plans. Participants also described a range of potential opportunities to improve hospital-based treatment of co-use that fall into 3 categories: (1) provider practice changes, (2) healthcare system changes, and (3) development and validation of clinical tools and treatment approaches. CONCLUSIONS: We identified unique challenges providing hospital addiction medicine care to patients who use both opioids and stimulants. These findings inform the development, implementation, and testing of hospital-based interventions for patients with co-use.

Cough elixir overdose causing toxic leuco-encephalopathy and serotonin syndrome.

Acute toxic leukoencephalopathy and serotonin syndrome are rare neurological complications associated with various drugs and toxins, some of which overlap. However, the co-occurrence of these conditions is poorly documented. We present the case of a 14-year-old boy who suddenly developed altered consciousness and autonomic dysfunction after consuming excessive quantities of cough remedies containing dextromethorphan, chlorphenamine, dichlorobenzyl alcohol, and amylmetacreson. Magnetic resonance imaging of the brain revealed distinct white matter lesions. With supportive care, the patient rapidly improved, and the magnetic resonance imaging abnormalities disappeared. The swift resolution, typical magnetic resonance imaging findings, and a history of exposure to drugs affecting the central nervous system's serotonergic system suggested concurrent acute toxic leukoencephalopathy and serotonin syndrome. The components of cough medications can be hazardous in overdose due to their potential to enhance serotonin toxicity and cause direct or indirect central nervous system white matter damage. Early recognition and appropriate treatment are essential for recovery.

Endocarditis, drug use and biological sex: A statewide analysis comparing sex differences in drug use-associated infective endocarditis with other drug-related harms.

OBJECTIVES: Hospitalizations for drug use-associated infective endocarditis (DUA-IE) have risen sharply across the United States over the past decade. The sex composition of DUA-IE remains less clear, and studies have indicated a possible shift to more females. We aimed to compare more recent statewide hospitalization rates for DUA-IE in females versus males and contextualize them among other drug-related harms in North Carolina (NC). METHODS: This study was a retrospective analysis using public health datasets of all NC hospital discharges for infective endocarditis from 2016 to 2020. Drug use-related hospitalizations were identified using ICD-10-CM codes. Discharge rates by year and sex for DUA-IE and non-DUA-IE were calculated and compared to fatal overdoses and acute hepatitis C (HCV). Temporal, demographic, and pregnancy trends were also assessed. RESULTS: Hospitalizations rates for DUA-IE were 9.7 per 100,000 over the five-year period, and 1.2 times higher among females than males. Females composed 57% of DUA-IE hospitalizations over the period. Conversely, fatal overdose, acute HCV, and non-DUA-IE hospitalization rates were higher among males. Age, county of residence, and pregnancy status did not explain the higher DUA-IE among females. CONCLUSION: Females now comprise the majority of DUA-IE hospitalizations in NC, unlike other drug-related harms. No clear demographic or geographic associations were found, and further research is needed to explain this phenomenon. Preventing invasive infections among females who inject drugs should be prioritized.

"I'm not going to lay back and watch somebody die": a qualitative study of how people who use drugs' naloxone experiences are shaped by rural risk environment and overdose education/naloxone distribution intervention.

BACKGROUND: Overdoses have surged in rural areas in the U.S. and globally for years, but harm reduction interventions have lagged. Overdose education and naloxone distribution (OEND) programs reduce overdose mortality, but little is known about people who use drugs' (PWUD) experience with these interventions in rural areas. Here, we analyze qualitative data with rural PWUD to learn about participants' experiences with an OEND intervention, and about how participants' perceptions of their rural risk environments influenced the interventions' effects. METHODS: Twenty-nine one-on-one, semi-structured qualitative interviews were conducted with rural PWUD engaged in the CARE2HOPE OEND intervention in Appalachian Kentucky. Interviews were conducted via Zoom, audio-recorded, and transcribed verbatim. Thematic analysis was conducted, guided by the Rural Risk Environment Framework. RESULTS: Participants' naloxone experiences were shaped by all domains of their rural risk environments. The OEND intervention transformed participants' roles locally, so they became an essential component of the local rural healthcare environment. The intervention provided access to naloxone and information, thereby increasing PWUDs' confidence in naloxone administration. Through the intervention, over half of participants gained knowledge on naloxone (access points, administration technique) and on the criminal-legal environment as it pertained to naloxone. Most participants opted to accept and carry naloxone, citing factors related to the social environment (responsibility to their community) and physical/healthcare environments (overdose prevalence, suboptimal emergency response systems). Over half of participants described recent experiences administering intervention-provided naloxone. These experiences were shaped by features of the local rural social environment (anticipated negative reaction from recipients, prior naloxone conversations). CONCLUSIONS: By providing naloxone paired with non-stigmatizing health and policy information, the OEND intervention offered support that allowed participants to become a part of the healthcare environment. Findings highlight need for more OEND interventions; outreach to rural PWUD on local policy that impacts them; tailored strategies to help rural PWUD engage in productive dialogue with peers about naloxone and navigate interpersonal conflict associated with overdose reversal; and opportunities for rural PWUD to formally participate in emergency response systems as peer overdose responders. Trial registration The ClinicalTrials.gov ID for the CARE2HOPE intervention is NCT04134767. The registration date was October 19th, 2019.

Toxic leukoencephalopathy versus delayed post-hypoxic leukoencephalopathy after oral morphine sulphate overdose.

Toxic leukoencephalopathy (TLE) is a rare pathology caused by various substances including opioids (notably heroin), immunosuppressants, chemotherapy agents, cocaine, alcohol and carbon monoxide. However, although heroin is metabolised by the body into morphine, there is a striking paucity in cases of primary oral morphine-induced TLE, especially in the adult population. We present the case of a man in his 40s admitted to hospital in respiratory depression with a Glasgow Coma Scale (GCS) score of 6 after taking an overdose of oral morphine sulphate. Following a complete recovery to baseline, he was then readmitted with an acute deterioration in his neurobehavioural condition. Initial investigations returned normal but MRI showed changes characteristic for TLE.In cases of opioid toxicity such as ours, TLE is difficult to differentiate from delayed post-hypoxic leukoencephalopathy, due to their similar clinical presentation, disease progression and radiological manifestation. We explore how clinicians can approach this diagnostic uncertainty.

Administration of andexanet alfa for traumatic intracranial hemorrhage in the setting of massive apixaban overdose: A case report.

PURPOSE: Apixaban is a direct-acting oral anticoagulant that selectively inhibits factor Xa. Reversal strategies utilized to treat factor Xa inhibitor-associated bleeding include andexanet alfa, prothrombin complex -concentrate (PCC), and activated PCC (aPCC). The optimal treatment of traumatic intracranial hemorrhage in the setting of an apixaban overdose is unknown. SUMMARY: This case report describes a 69-year-old female who initially presented to an emergency department at a community hospital due to a ground-level fall with traumatic intracranial hemorrhage. The patient reportedly ingested apixaban 275 mg, carvedilol 250 mg, atorvastatin 1,200 mg, and unknown amounts of amlodipine and ethanol. Anti-inhibitor coagulant complex, an aPCC, was administered approximately 3 hours after presentation. Initial thromboelastography performed approximately 4 hours after presentation showed a prolonged reaction time of 16.8 minutes. Ongoing imaging and evidence of coagulopathy prompted repeated aPCC administration to a cumulative dose of approximately 100 U/kg. The patient underwent craniotomy with hematoma evacuation. Postoperative imaging showed expansion of the existing intracranial hemorrhage and new areas of hemorrhage. Andexanet alfa was administered approximately 18 hours after presentation, followed by repeat craniotomy with evacuation of the hematoma. No further expansion of the intracranial hemorrhage was observed, and the reaction time on thromboelastography was normalized at 6.3 minutes. CONCLUSION: This case suggests that andexanet alfa may have a role in the management of traumatic hemorrhage in the setting of an acute massive apixaban overdose. Use of andexanet alfa, PCC, and aPCC in this context requires further research.

Amitriptyline overdose-an uncommon cause of acute transient exotropia presenting to the emergency setting: a case report.

BACKGROUND: Acute presentations of acquired exotropia or divergent alignment of either or both eyes are commonly observed following intracranial vascular events, trauma, orbital, and endoscopic sinus surgeries. CASE PRESENTATION: The reported case is about a 16-year-old previously healthy Tamil female who presented to the emergency department with a few hours of reduced responsiveness. With the only clue in the history being about a family conflict the previous day, the examination revealed a noticeable exotropia along with a constellation of anticholinergic findings: a low Glasgow Coma Score, mydriasis, tachycardia, floppy limbs, exaggerated reflexes, and a palpable urinary bladder. Amitriptyline overdose leading to significant neurological involvement was suspected, and she was immediately offered urine alkalinization. Resources for urine and blood toxicological studies were not available. The patient gained consciousness 24 hours later and confirmed an overdose of ten amitriptyline tablets. Exotropia, a unique manifestation of this patient's neurotoxicity, spontaneously resolved in 36 hours. DISCUSSION AND CONCLUSIONS: The reported case is about an uncommon clinical finding of exotropia seen in a common toxicological emergency: acute amitriptyline overdose. The importance of having a wide knowledge of various clinical presentations of drug toxicities is highlighted here, as any delay in diagnosis or initiation of life-saving measures could have resulted in fatal consequences.

Differential risks of syringe service program participants in Central Ohio: a latent class analysis.

BACKGROUND: Significant heterogeneity exists among people who use drugs (PWUD). We identify distinct profiles of syringe service program (SSP) clients to (a) evaluate differential risk factors across subgroups and (b) inform harm reduction programming. METHODS: Latent class analysis (LCA) was applied to identify subgroups of participants (N = 3418) in a SSP in Columbus, Ohio, from 2019 to 2021. Demographics (age, sex, race/ethnicity, sexual orientation, housing status) and drug use characteristics (substance[s] used, syringe gauge, needle length, using alone, mixing drugs, sharing supplies, reducing use, self-reported perceptions on the impact of use, and treatment/support resources) were used as indicators to define latent classes. A five-class LCA model was developed, and logistic regression was then employed to compare risk factors at program initiation and at follow-up visits between latent classes. RESULTS: Five latent classes were identified: (1) heterosexual males using opioids/stimulants with housing instability and limited resources for treatment/support (16.1%), (2) heterosexual individuals using opioids with stable housing and resources for treatment/support (33.1%), (3) individuals using methamphetamine (12.4%), (4) young white individuals using opioids/methamphetamine (20.5%), and (5) females using opioids/cocaine (17.9%). Class 2 served as the reference group for logistic regression models, and at the time of entry, class 1 was more likely to report history of substance use treatment, overdose, HCV, sharing supplies, and mixing drugs, with persistently higher odds of sharing supplies and mixing drugs at follow-up. Class 3 was more likely to report history of overdose, sharing supplies, and mixing drugs, but outcomes at follow-up were comparable. Class 4 was the least likely to report history of overdose, HCV, and mixing drugs, but the most likely to report HIV. Class 5 was more likely to report history of substance use treatment, overdose, HCV, sharing supplies, and mixing drugs at entry, and higher reports of accessing substance use treatment and testing positive for HCV persisted at follow-up. CONCLUSIONS: Considerable heterogeneity exists among PWUD, leading to differential risk factors that may persist throughout engagement in harm reduction services. LCA can identify distinct profiles of PWUD accessing services to tailor interventions that address risks, improve outcomes, and mitigate disparities.

Drug checking in the fentanyl era: Utilization and interest among people who inject drugs in San Diego, California.

BACKGROUND: In North America, overdose rates have steeply risen over the past five years, largely due to the ubiquity of illicitly manufactured fentanyls in the drug supply. Drug checking services (DCS) represent a promising harm reduction strategy and characterizing experiences of use and interest among people who inject drugs (PWID) is a priority. METHODS: Between February-October 2022, PWID participating in a cohort study in San Diego, CA and Tijuana, Mexico completed structured surveys including questions about DCS, socio-demographics and substance use behaviors. We used Poisson regression to assess factors associated with lifetime DCS use and characterized experiences with DCS and interest in free access to DCS. RESULTS: Of 426 PWID, 72% were male, 59% Latinx, 79% were experiencing homelessness and 56% ever experienced a nonfatal overdose. One third had heard of DCS, of whom 57% had ever used them. Among the latter, most (98%) reported using fentanyl test strips (FTS) the last time they used DCS; 66% did so less than once per month. In the last six months, respondents used FTS to check methamphetamine (48%), heroin (30%) or fentanyl (29%). Relative to White/non-Latinx PWID, those who were non-White/Latinx were significantly less likely to have used DCS [adjusted risk ratio (aRR): 0.22; 95% CI: 0.10, 0.47), as were PWID experiencing homelessness (aRR:0.45; 95% CI: 0.28, 0.72). However, a significant interaction indicated that non-White/Latinx syringe service program (SSP) clients were more likely to have used DCS than non-SSP clients (aRR: 2.79; CI: 1.09, 7.2). Among all PWID, 44% expressed interest in free access to FTS, while 84% (of 196 PWID) expressed interest in advanced spectrometry DCS to identify and quantify multiple substances. CONCLUSIONS: Our findings highlight low rates of DCS awareness and utilization, inequities by race/ethnicity and housing situation, high interest in advanced spectrometry DCS versus FTS, and the potential role of SSPs in improving access to DCS, especially among racial/ethnic minorities.

Delayed-Onset Losartan-Induced Pancreatitis Secondary to an Overdose: A Case Report.

Acute pancreatitis is defined as inflammation of the pancreas and is most commonly caused by gallstones and alcohol use. Less commonly, acute pancreatitis can be drug induced from medications that are divided into 5 subgroups (classes Ia-V). The subgroups are determined based on the cases reported, reaction with rechallenge and a consistent period of latency. We describe a case of a 34-year-old female who overdosed on losartan pills in a suicide attempt but developed symptoms of drug-induced acute pancreatitis nearly a week later without gallstones, alcohol involvement, or other drug toxicity.

Psychosis Related to Baclofen Withdrawal or Overdose: A Systematic Review.

OBJECTIVE: To systematically review case reports of psychosis related to withdrawal or overdose of baclofen, which is a gamma-aminobutyric acid (GABA) B agonist. METHODS: PubMed, MEDLINE, CINAHL, and PsychINFO were searched to identify articles related to psychosis secondary to withdrawal or overdose of baclofen using the terms 'baclofen' and ' psychosis'. Comparisons were made between cases in terms of concomitant antipsychotic use, diagnosis of delirium, and evidence of association. Quality of case reports was assessed using the CARE Case Report Guidelines checklist. RESULTS: In total, 34 patients from 28 case reports were reviewed. Twenty-three patients experienced psychosis upon baclofen withdrawal; among them, 18 had resolution of psychosis upon reinitiation of baclofen, whereas antipsychotic monotherapy was less successful (only four of eight patients responded). An additional baclofen withdrawal period led to recurrence of psychotic symptoms in four of seven patients. Eleven patients had psychosis on induction or after overdose of baclofen; among them, four patients had resolution of psychosis upon cessation of baclofen. The mean quality of the case reports was 6.4 of 13. CONCLUSION: Considering its GABAergic agonism, along with evidence of psychosis on induction or withdrawal, baclofen may have some antipsychotic and pro-psychotic properties.

Higher buprenorphine dose associated with increased treatment retention at low threshold buprenorphine clinic: A retrospective cohort study.

INTRODUCTION: Controversy exists regarding effective sublingual buprenorphine dosing for treatment of opioid use disorder (OUD), leading to dose caps of 16 mg per day. The Project Connections at Re-Entry (PCARE) program is a low-threshold buprenorphine clinic that provides medication for OUD to vulnerable populations in Baltimore City. OBJECTIVES: To compare retention in care based on treatment dose of buprenorphine, and to examine associated population characteristics. METHODS: This analysis includes clinical patients who received buprenorphine treatment at PCARE between January and July 2021. The study categorized patients into two dosing groups (16 mg or >16 mg). We conducted chi-square tests of independence for categorical variables and independent sample t-tests for continuous variables to evaluate any significant differences in demographic and clinical characteristics by dosing category. To examine differences in 30- and 90-day retention, we conducted multivariable logistic regression analyses with the outcome variable defined as successful retention (at 30 and 90 days, respectively) controlling for demographic and clinical characteristics. RESULTS: In the study period, 566 patients received buprenorphine treatment at the PCARE van. Patients were primarily male (70.9 %), Black (89.4 %), had a mean age of 46.3 years (SD = 11.5), and a mean opioid use of 22.1 years (SD = 13.5). The majority had previous criminal justice involvement (73.9 %), Medicaid insurance coverage (75.4 %), and were unemployed (69.6 %). Nearly half of the sample had reported a previous overdose event (48.4 %). The study found no significant demographic differences between patients receiving 16 mg of buprenorphine per day compared to patients receiving >16 mg. Patients receiving >16 mg had significantly higher rates of treatment retention at 30 and 90 days: 95.4 % vs 86.7 % (p = 0.001), and 82.7 % vs. 67.6 % (p < 0.001) than those receiving 16 mg, respectively. In a multivariable logistic regression controlling for demographic and drug use characteristics, odds of 30-day (Adjusted Odds Ratio [AOR] = 3.98, 95 % Confidence Interval [CI] = 1.92, 8.74, p < 0.001) and 90-day retention (AOR = 2.56, 95 % CI = 1.55, 4.22, p < 0.001) were greater among patients receiving >16 mg daily compared to 16 mg. CONCLUSIONS: In this study examining patients with OUD in a low-threshold buprenorphine clinic, we observed higher rates of treatment retention with buprenorphine doses >16 mg.

Fentanyl overdose concerns among people who inject drugs: The role of sex, racial minority status, and overdose prevention efforts.

BACKGROUND: People who inject drugs (PWID) have an elevated risk of fentanyl-related overdoses. This study explores fentanyl overdose concerns among PWID and the role of sex, racial minority status, and overdose prevention efforts in these concerns. METHOD: Data were from 498 PWID from Baltimore City, MD, recruited using street-based outreach between 2016 and 2019. Multinomial logistic regressions assessed correlates of participants' level of concern for themselves and their peers overdosing from fentanyl. RESULTS: A third of participants were female, half were Black, over two-thirds perceived fentanyl to be in all/most of heroin, 40% expressed low fentanyl overdose concern, and a third overdosed in the past 6 months. After controlling for sociodemographic characteristics, female sex was associated with being very concerned about fentanyl overdoses for oneself (adjusted relative risk [aRR]: 2.13; 95% CI: 1.22, 3.72) and peers (aRR: 1.98; 95% CI: 1.14, 3.45). Compared to Black participants, White participants were less likely to be very concerned about fentanyl overdoses for themselves (aRR: 0.35; 95% CI: 0.19, 0.65). Participants who often/always carried naloxone (aRR: 2.91; 95% CI: 1.42, 5.95) perceived fentanyl in most heroin (aRR: 2.78; 95% CI: 1.29, 5.97) or were on medications for opioid use disorder (MOUD) (quite a bit concerned aRR: 2.18; 95% CI: 1.28, 3.69; very concerned: aRR: 1.96; 95% CI: 1.19, 3.22) were more likely than their counterparts to report being concerned for their peers, but not for themselves. CONCLUSION: Female sex and racial minority status were associated with greater concern regarding fentanyl overdoses for oneself. Increasing overdose deaths in these populations suggests disparate access to harm-reduction initiatives rather than interest or concern. Furthermore, findings on naloxone, MOUD, and concerns for peers support social network-based interventions among PWID. (PsycInfo Database Record (c) 2023 APA, all rights reserved).