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3.
Harm Reduct J ; 21(1): 5, 2024 Jan 06.
Article in English | MEDLINE | ID: mdl-38184576

ABSTRACT

BACKGROUND: With growing rates of unregulated drug toxicity death and concerns regarding COVID-19 transmission among people who use drugs, in March 2020, prescribed safer supply guidance was released in British Columbia. This study describes demographic and substance use characteristics associated with obtaining prescribed safer supply and examines the association between last 6-month harm reduction service access and obtaining prescribed safer supply. METHODS: Data come from the 2021 Harm Reduction Client Survey administered at 17 harm reduction sites across British Columbia. The sample included all who self-reported use of opioids, stimulants, or benzodiazepines in the prior 3 days (N = 491), given active use of these drugs was a requirement for eligibility for prescribed safer supply. The dependent variable was obtaining a prescribed safer supply prescription (Yes vs. No). The primary independent variables were access to drug checking services and access to overdose prevention services in the last 6 months (Yes vs. No). Descriptive statistics (Chi-square tests) were used to compare the characteristics of people who did and did not obtain a prescribed safer supply prescription. Multivariable logistic regression models were run to examine the association of drug checking services and overdose prevention services access with obtaining prescribed safer supply. RESULTS: A small proportion (n = 81(16.5%)) of the sample obtained prescribed safer supply. After adjusting for gender, age, and urbanicity, people who reported drug checking services access in the last 6 months had 1.67 (95% CI 1.00-2.79) times the odds of obtaining prescribed safer supply compared to people who had not contacted these services, and people who reported last 6 months of overdose prevention services access had more than twice the odds (OR 2.08 (95% CI 1.20-3.60)) of prescribed safer supply access, compared to people who did not access these services. CONCLUSIONS: Overall, the proportion of respondents who received prescribed safer supply was low, suggesting that this intervention is not reaching all those in need. Harm reduction services may serve as a point of contact for referral to prescribed safer supply. Additional outreach strategies and service models are needed to improve the accessibility of harm reduction services and of prescribed safer supply in British Columbia.


Subject(s)
Drug Overdose , Harm Reduction , Humans , Cross-Sectional Studies , Analgesics, Opioid , Benzodiazepines , British Columbia , Drug Overdose/prevention & control
4.
Am J Prev Med ; 66(1): 10-17, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37633426

ABSTRACT

INTRODUCTION: The proliferation of fentanyl and its analogs in illegal, unregulated drug markets remains a major driver of the overdose crisis in North America. Drug checking services have been implemented as a harm reduction strategy to address the crisis. However, little is known about their potential utility as a mechanism for monitoring population-level risk of overdose stemming from changing fentanyl concentration in unregulated drugs over time. Therefore, this study assessed the relationship between median fentanyl concentration in expected opioid drug checking samples and the death rate due to illicit drug toxicity over time in Vancouver, Canada. METHODS: Monthly population-based rates of death due to illicit drug toxicity were drawn from provincial coroner records. Monthly median percent fentanyl concentration was calculated using a validated quantification model from point-of-care Fourier-transform infrared spectra among expected opioid samples that tested positive for fentanyl at community drug checking services. A time-series analysis using generalized additive modeling was conducted to examine the association between monthly median fentanyl concentration and monthly death rate due to illicit drug toxicity, controlling for calendar month. Analyses were conducted in 2021-2022. RESULTS: Between January 2019 and October 2020, 577 deaths due to illicit drug toxicity occurred in Vancouver, and the observed monthly rate ranged from 1.75 to 7.65 deaths per 100,000 population. A significant, positive association was observed between monthly median fentanyl concentration and monthly death rate due to illicit drug toxicity, adjusting for calendar month (chi-square=52.21, p<0.001). CONCLUSIONS: Findings suggest a role for point-of-care drug checking as a tool for monitoring evolving overdose risk at the population level.


Subject(s)
Drug Overdose , Drug-Related Side Effects and Adverse Reactions , Illicit Drugs , Humans , Fentanyl , Analgesics, Opioid/adverse effects , Heroin , Drug Overdose/epidemiology , Canada/epidemiology
5.
Int J Drug Policy ; 123: 104290, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38101275

ABSTRACT

OBJECTIVE: Responding to increasing rates of illicit drug toxicity mortality in British Columbia, regional health authorities introduced various types and models of drug checking services starting in 2016. Uptake has been gradual yet consistent, but motivators and barriers of service use have not been well-described. METHODS: The British Columbia Harm Reduction Client Survey is a cross-sectional survey conducted at harm reduction sites across British Columbia. Data for the present findings were collected between March 2021 and January 2022. Participants (n = 537) were asked about their use of drug checking services and what prevented them from using available services. Responses were analyzed with descriptive statistics and multivariable logistic regression. RESULTS: Of all participants, 519 (96.6 %) answered the survey question on drug checking with 144 (27.7 %) reporting having used services within six months. Participants highlighted barriers such as not knowing where to access services (21.0 %), or not having services in their area (10.0 %). Among people who did not report recent use of fentanyl, 49.6 % stated they would not use their drugs if they tested positive for fentanyl. Other harm reduction behaviors were positively associated with drug checking, such as use of overdose prevention sites (adjusted odds ratio [AOR]: 2.75, 95 % confidence interval [CI]: 1.65, 4.59) and having a naloxone kit (AOR: 2.67, 95 %CI: 1.14, 6.28). Receipt of opioid agonist therapy in the previous six months was also positively associated with drug checking (AOR: 1.72, 95 %CI: 1.05, 2.83). DISCUSSION: Drug checking uptake remains low in British Columbia, however this study identified desire for services among participants, suggesting a need for expanded drug checking services. Behavioral change was reported among a high proportion of people who said they would not use their drugs if they tested positive for fentanyl, meaning that immunoassay strips alone have utility in the context of a pervasive fentanyl supply.


Subject(s)
Drug Overdose , Fentanyl , Humans , British Columbia/epidemiology , Cross-Sectional Studies , Drug Overdose/epidemiology , Drug Overdose/prevention & control , Surveys and Questionnaires , Harm Reduction , Analgesics, Opioid
6.
Harm Reduct J ; 20(1): 178, 2023 Dec 13.
Article in English | MEDLINE | ID: mdl-38093272

ABSTRACT

INTRODUCTION: Lives lost in North America due to the unregulated drug poisoning emergency are preventable and those who survive an opioid overdose may suffer long-term disability. Rates of opioid overdose more than doubled following the onset of the COVID-19 pandemic in British Columbia, Canada. MATERIALS AND METHODS: Our analytical sample was comprised of 1447 participants from the 2018, 2019, and 2021 Harm Reduction Client Survey who responded yes or no to having experienced an opioid overdose in the past 6 months. Participants were recruited from harm reduction sites from across British Columbia. We used logistic regression to explore associations of experiencing an opioid overdose. RESULTS: Overall, 21.8% of participants reported experiencing an opioid overdose in the last six months (18.2% in 2019 and 26.6% in 2021). The following factors were positively associated with increased adjusted odds of experiencing a non-fatal opioid overdose: cis men relative to cis women (AOR 1.49, 95% CI 1.10-2.02), unstably housed compared to people with stable housing (AOR 1.87, 95% CI 1.40-2.50), and participants from 2021 compared to those from 2019 (AOR 3.06, 95% CI 1.57-5.97). The effects of both previous experience of a stimulant overdose and having witnessed an opioid overdose depended on the year of study, with both effects decreasing over subsequent years. CONCLUSIONS: Overdoses have increased over time; in 2021 more than one in four participants experienced an overdose. There is an urgent need for policy and program development to meaningfully address the unregulated drug poisoning emergency through acceptable life-saving interventions and services to prevent overdoses and support overdose survivors.


Subject(s)
Drug Overdose , Opiate Overdose , Male , Humans , Female , British Columbia/epidemiology , Opiate Overdose/epidemiology , Cross-Sectional Studies , Fentanyl , Pandemics , Drug Overdose/prevention & control , Analgesics, Opioid/therapeutic use
7.
Am J Drug Alcohol Abuse ; 49(6): 685-690, 2023 11 02.
Article in English | MEDLINE | ID: mdl-37506334

ABSTRACT

Drug checking services provide individuals who use drugs with the ability to test samples of their drugs for the presence of highly potent substances. However, there has been recent concern about whether the existing repertoire of point-of-care drug checking technologies, such as immunoassay strips and Fourier-transform infrared spectroscopy (FTIR), are adequate in identifying substances in the unregulated drug supply. Carfentanil and nitazene opioids, substances that are even more potent than fentanyl in vitro, have been found in the unregulated supply in North America and pose a challenge to our existing drug checking strategy. For example, etizolam has recently permeated the unregulated drug supply in North America, and has demonstrated the ability to evade point-of-care drug checking technologies. In response to the incessantly changing nature of the unregulated supply, we argue that drug checking technologies and service delivery models must continuously adapt alongside constantly changing drug markets. We provide two examples of emerging technologies, paper spray-mass spectrometry and surface-enhanced Raman spectroscopy, which address many of the shortcomings of existing technologies. For both technologies, we discuss their feasibility, where they can be offered, their advantages, and how they address gaps in our existing technologies. We contend that these technologies, and other emerging technologies, can be integrated into a future approach to drug checking that flexibly uses different technologies and service delivery methods to adapt to changes in the drug supply.


Subject(s)
Drug Overdose , Illicit Drugs , Humans , Pharmaceutical Preparations , Harm Reduction , Analgesics, Opioid/analysis , Illicit Drugs/analysis
8.
PLoS One ; 18(7): e0288656, 2023.
Article in English | MEDLINE | ID: mdl-37440523

ABSTRACT

INTRODUCTION: Increasingly, Fourier-transform infrared (FTIR) spectroscopy is being used as a harm reduction tool to provide people who use drugs real-time information about the contents of their substances. However, FTIR spectroscopy has been shown to have a high detection limit for fentanyl and interpretation of results by a technician can be subjective. This poses concern, given that some synthetic opioids can produce serious toxicity at sub-detectable levels. The objective of this study was to develop a neural network model to identify fentanyl and related analogues more accurately in drug samples compared to traditional analysis by technicians. METHODS: Data were drawn from samples analyzed point-of-care using combination FTIR spectroscopy and fentanyl immunoassay strips in British Columbia between August 2018 and January 2021. We developed neural network models to predict the presence of fentanyl based on FTIR data. The final model was validated against the results from immunoassay strips. Prediction performance was assessed using F1 score, accuracy, and area under the receiver-operating characteristic curve (AUROC), and was compared to results obtained from analysis by technicians. RESULTS: A total of 12,684 samples were included. The neural network model outperformed results from those analyzed by technicians, with an F1 score of 96.4% and an accuracy of 96.4%, compared to 78.4% and 82.4% with a technician, respectively. The AUROC of the model was 99.0%. Fentanyl positive samples correctly detected by the model but not by the technician were typically those with low fentanyl concentrations (median: 2.3% quantity by weight; quartile 1-3: 0.0%-4.6%). DISCUSSION: Neural network models can accurately predict the presence of fentanyl and related analogues using FTIR data, including samples with low fentanyl concentrations. Integrating this tool within drug checking services utilizing FTIR spectroscopy has the potential to improve decision making to reduce the risk of overdose and other negative health outcomes.


Subject(s)
Drug Overdose , Fentanyl , Humans , Analgesics, Opioid , British Columbia , Neural Networks, Computer
9.
Drug Alcohol Rev ; 42(3): 538-543, 2023 03.
Article in English | MEDLINE | ID: mdl-36423900

ABSTRACT

INTRODUCTION: The emergence of fentanyl and its analogues have contributed to a drastic rise in overdose-related mortality in recent years. The objective of this study was to determine the number of drug checking samples containing fentanyl and fentanyl analogues using both point of care and confirmatory drug checking technologies. METHODS: Point-of-care drug checking data, using a combination of fentanyl immunoassay strips and Fourier-transform infrared spectroscopy (FTIR), were collected at harm reduction sites in Vancouver and Surrey, British Columbia. Based on current recommendations from the British Columbia Centre on Substance Use Drug Checking Project, a subset of these samples was sent for confirmatory analysis using quantitative nuclear resonance spectroscopy, gas chromatography-mass spectrometry and/or liquid chromatography-mass spectrometry. RESULTS: A total of 22,916 samples were tested using FTIR and fentanyl immunoassay strips, of which 6125 (29%) were positive for fentanyl and/or fentanyl analogues. FTIR identified a fentanyl analogue in five samples (all carfentanil). Of the 1467 samples sent for confirmatory analysis, fentanyl was identified in 855 (58%) and fentanyl analogues in 85 (6%), including: carfentanil (n = 56), acetyl fentanyl (n = 15), furanyl fentanyl (n = 9) and cyclopropyl fentanyl (n = 5). DISCUSSION AND CONCLUSION: Our research found that FTIR does not consistently distinguish between fentanyl and its analogues at point of care and that highly sensitive confirmatory drug checking technologies are needed to identify fentanyl analogues. These findings underscore the limitations of current drug checking technologies and the importance of using both point of care and confirmatory drug checking initiatives for monitoring changes in the drug supply.


Subject(s)
Drug Overdose , Fentanyl , Humans , British Columbia , Gas Chromatography-Mass Spectrometry , Spectroscopy, Fourier Transform Infrared/methods , Analgesics, Opioid/analysis
10.
Int J Drug Policy ; 105: 103707, 2022 07.
Article in English | MEDLINE | ID: mdl-35504093

ABSTRACT

BACKGROUND: Increased drug-related harms, including overdoses (poisonings), have been reported in the days around income assistance payments, yet little is known about changes in the unregulated drug supply during this time. In this exploratory analysis, we investigated whether changes in the unregulated opioid drug supply are associated with income assistance payment weeks. METHODS: Using data from drug checking services in Vancouver, BC, we conducted modified Poisson and linear regression models to examine the association between income assistance payment weeks and three key outcomes: (1) proportion of fentanyl positivity among expected opioid samples, (2) fentanyl concentration among fentanyl-positive expected opioid samples, and (3) proportion of benzodiazepine positivity among expected opioid samples. RESULTS: Between October 2017 and December 2019, 4306 (90.41%) of expected opioid samples tested positive for fentanyl, and the median fentanyl concentration was 7.0% (quartile [Q]1 - Q3: 5.1% - 9.8%). Income assistance payment week was associated with an increased prevalence of fentanyl positivity among expected opioid samples (prevalence ratio [PR]: 1.03; 95% confidence interval [CI]: 1.00, 1.05); however, we failed to find a statistically significant association between income assistance payment week and fentanyl concentration (regression coefficient: 0.70; 95% CI: 0.44, 1.09). Additionally, income assistance payment week was associated with an increased prevalence of benzodiazepine positivity among expected opioid samples (PR: 1.86; 95% CI: 1.07, 3.24). CONCLUSION: These findings suggest that during income assistance payment weeks, there may be more fentanyl and benzodiazepines circulating in the unregulated opioid drug supply. The rise in fentanyl and benzodiazepine-adulterated opioids during income assistance payment weeks may be contributing to the increase in illicit drug overdoses seen during this time of the month.


Subject(s)
Drug Overdose , Illicit Drugs , Analgesics, Opioid , Benzodiazepines/therapeutic use , Canada/epidemiology , Drug Overdose/drug therapy , Drug Overdose/epidemiology , Fentanyl , Humans , Illicit Drugs/analysis
11.
Acta Neurol Belg ; 122(6): 1537-1545, 2022 Dec.
Article in English | MEDLINE | ID: mdl-34595730

ABSTRACT

OBJECTIVE: To retrospectively evaluate the clinical outcome of six patients with skull base hemangiopericytomas (HPCs) and that of a cohort of 37 similar patients identified by a systematic review of the literature. METHODS: The series constitutes of three men and three women with newly diagnosed skull base HPC who underwent multimodal treatment including surgery, external beam radiotherapy (EBRT) and pre-operative embolization. Furthermore, a systematic review off the literature identified 37 reports of primarily intracranial skull base HPCs. RESULTS: Four patients had a gross total resection (GTR) and two patients had a near total resection. Five patients were referred for adjuvant EBRT with a survival ranging from 15 to 47 months. All patients had an excellent outcome and resumed their previous activities. Literature review identified 37 additional patients with skull base HPC. Altogether, tumors were unevenly distributed above and below tentorium. GTR was achieved in half the patients, and 72.1% were referred to EBRT. Out of 37 reported patients in the literature, survival longer than 1 year was described in only 24. Within the combined cohort including the present series, survival was 83.6 months. CONCLUSIONS: The present series shows that a radical resection of HPC can be achieved under the difficult anatomical conditions of skull base surgery. Pre-operative arterial embolization may be instrumental to maintain a clear visual field and prevent excessive blood loss. Finally, the results of the present cohort suggest that EBRT may be useful for local growth control, as an effective palliative measure for skull base HPCs.


Subject(s)
Hemangiopericytoma , Male , Humans , Female , Retrospective Studies , Hemangiopericytoma/diagnostic imaging , Hemangiopericytoma/surgery , Neurosurgical Procedures/methods , Combined Modality Therapy , Skull Base/surgery , Skull Base/pathology , Treatment Outcome
12.
Am J Epidemiol ; 191(2): 241-247, 2022 01 24.
Article in English | MEDLINE | ID: mdl-33977304

ABSTRACT

North America has been contending with an unregulated street drug supply in which opioids are often adulterated with illicitly manufactured fentanyl. The unpredictability of composition may result in an increased risk of overdose due to unexpected elevated concentrations of the high-potency drug. Using data from a community-based drug-checking project, we evaluated trends in fentanyl concentration of illicit opioids in the context of an overdose epidemic. Using a quantification model for fentanyl hydrochloride, historical Fourier-transform infrared spectra from opioid drug-checking samples were analyzed to determine fentanyl concentrations. Median monthly fentanyl concentrations were plotted, and polynomial and autoregressive time-series analyses were performed to examine trends over time. A total of 3,621 fentanyl-positive samples were included in the study, spanning November 2017 to December 2019. Monthly median fentanyl concentrations ranged from 4.5% to 10.4%. Time-series analyses indicated that a third-degree polynomial model fit the data well (R2 = 0.639), suggesting a cyclical pattern in median concentration over time. Notably, absolute variance in fentanyl concentration decreased by an average 0.1% per month (P < 0.001). Future research should explore the relationship between fentanyl concentration and overdose to identify potential targeted harm-reduction interventions that can respond to changes in observed fentanyl concentration.


Subject(s)
Analgesics, Opioid/chemistry , Drug Contamination , Fentanyl/analysis , Illicit Drugs/chemistry , Canada , Humans , Time Factors
14.
Drug Alcohol Depend ; 228: 108976, 2021 11 01.
Article in English | MEDLINE | ID: mdl-34536717

ABSTRACT

BACKGROUND: Opioid overdose deaths in the United States continue to rise, with the majority of deaths involving fentanyl. Drug checking has been used in Europe and Canada to assess adulteration of the illegal drug supply, but faces legal barriers in the United States. We are presenting information from a pilot mobile program offering drug checking services to participants of a harm reduction program in Chicago, Illinois, USA. METHODS: Drug checking services were provided at five mobile outreach and one fixed-point drop-in location in Chicago, IL, between March 2019 and August 2020. Three technologies were used: a Fourier transform infrared spectroscopy (FTIR) spectrometer, a handheld high-pressure mass spectrometer (HPMS), and immunoassay fentanyl test strips (FTS). We report on results generated by this combination of technology during the study period. RESULTS: During the study period, 422 total samples were tested, the majority of which were sold as dope/heroin (66.7 %). Of the 282 samples sold as dope/heroin, 12.8 % matched to fentanyl on the FTIR, 47.5 % had fentanyl identified on the HPMS, and 57.8 % produced a positive FTS. CONCLUSIONS: This pilot program demonstrated the feasibility of using three technologies to assess for the presence of fentanyl in user-submitted samples, revealed discordant results from the technologies, and provided information on the local drug market.


Subject(s)
Drug Overdose , Illicit Drugs , Analgesics, Opioid , Chicago , Fentanyl , Humans , Illinois , Pilot Projects , Technology , United States
15.
Harm Reduct J ; 18(1): 66, 2021 06 27.
Article in English | MEDLINE | ID: mdl-34176497

ABSTRACT

BACKGROUND: Drug checking is a harm reduction intervention aiming to reduce substance use-related risks by improving drug user knowledge of the composition of unregulated drugs. With increasing fears of fentanyl adulteration in unregulated drugs, this study sought to examine whether the expected type of drug checked (stimulant vs. opioid) was associated with timing of drug checking service utilization (pre-consumption vs. post-consumption). METHODS: Data were derived from drug checking sites in British Columbia between October 31, 2017 and December 31, 2019. Pearson's Chi-square test was used to examine the relationship between expected sample type (stimulant vs. opioid) and timing of service utilization. Odds ratios (OR) were calculated to assess the strength of this relationship. The Mantel-Haenszel (MH) test was used to adjust for service location. RESULTS: A total of 3561 unique stimulant and opioid samples were eligible for inclusion, including 691 (19.40%) stimulant samples; and 2222 (62.40%) samples that were tested pre-consumption. Results indicated a positive association between testing stimulant samples and testing pre-consumption (OR = 1.45; 95% CI 1.21-1.73). Regions outside of the epicenter of the province's drug scene showed a stronger association with testing pre-consumption (ORMH = 2.33; 95% CI 1.51-3.56) than inside the epicenter (ORMH = 1.33; 95% CI 1.09-1.63). CONCLUSION: Stimulant samples were more likely to be checked pre-consumption as compared with opioid samples, and stimulant samples were more likely to be tested pre-consumption in regions outside the epicenter of the province's drug scene. This pattern may reflect a concern for fentanyl-adulterated stimulant drugs.


Subject(s)
Drug Overdose , Pharmaceutical Preparations , Analgesics, Opioid , Cross-Sectional Studies , Fentanyl , Humans
16.
Int J Drug Policy ; 93: 103169, 2021 07.
Article in English | MEDLINE | ID: mdl-33627302

ABSTRACT

BACKGROUND: From mid-2018, an increase in novel psychoactive substance (NPS) benzodiazepines was noted on surveillance of the unregulated drug market around Vancouver, British Columbia, Canada. The rise was concordant with an outbreak of atypical overdoses suspicious for benzodiazepine adulteration of unregulated opioids. This study sought to describe the number and type of NPS benzodiazepines in a sample drawn from a community drug checking program during this period, and to explore accuracy of point-of-care drug checking technologies when compared to confirmatory methods in this sample. METHODS: Point-of-care drug checking data using fentanyl and benzodiazepine test strips as well as Fourier transform infrared spectroscopy were gathered at harm reduction sites in the Vancouver area from October 2018 to January 2020. A convenience subsample underwent confirmatory testing with gas chromatography-mass spectrometry, liquid chromatography-mass spectrometry, or quantitative nuclear magnetic resonance spectroscopy. RESULTS: Of 159 samples with both point-of-care and confirmatory results, 24 (15.1%) contained at least one NPS benzodiazepine, including etizolam (n = 18), flubromazolam (n = 3), flualprazolam (4), and flubromazepam (n = 1). Of 114 confirmatory samples expected by participants on self-report to contain opioids, 18 (15.8%) contained some NPS benzodiazepine, with 16 (14.0%) containing both an NPS benzodiazepine and an opioid, always fentanyl. False positive and negative rates were 15.5% and 37.5% for test strips, and 3.9% and 91.7% for FTIR, respectively. Combined together, false positive and negative rates of point-of-care methods were 17.8% and 29.2%. CONCLUSIONS: NPS benzodiazepine adulteration in an unregulated drug supply sample reveals new risks compounding ongoing harms associated with the synthetic opioid epidemic. Given substantial false positive and false negative rates noted in our sample for point-of-care detection methods, cautious use of combined point-of-care methods, routinely paired with confirmatory drug checking may aid in early detection and monitoring of unregulated drug markets and inform targeted harm reduction strategies and health policy approaches.


Subject(s)
Drug Overdose , Pharmaceutical Preparations , Analgesics, Opioid/adverse effects , Benzodiazepines/adverse effects , British Columbia/epidemiology , Disease Outbreaks , Drug Overdose/epidemiology , Humans , Point-of-Care Systems
17.
Subst Abus ; 42(4): 775-779, 2021.
Article in English | MEDLINE | ID: mdl-33617730

ABSTRACT

Background: With the emergence of unregulated fentanyl, people who use unregulated opioids are increasingly relying on appearance in an effort to ascertain the presence of fentanyl and level of drug potency. However, the utility of visual inspection to identify drug composition in the fentanyl era has not been assessed. Methods: We assessed client expectation, appearance, and composition of street drug samples being presented for drug checking. Results of a visual screening test were compared to fentanyl immunoassay strip testing. We calculated sensitivity, specificity and likelihood ratios (LR) to assess the accuracy of the common assumption that samples with a "pebbles" appearance contain fentanyl. Results: In total, of the 2502 unregulated opioid samples tested, 1820 (73.5%) appeared as "pebbles", of which 1729 (95.0%) tested positive for fentanyl for a sensitivity of 75.9% (95% Confidence Interval [CI]: 74.2-77.6) and specificity of 59.4% (95%CI: 57.5-61.3). Although, the odds of samples containing fentanyl was 4.60 (95%CI: 3.47-6.11) times higher among pebbles samples compared to non-pebble samples, the positive LR for pebbles to contain fentanyl was only 1.87 (CI: 1.59-2.19). The negative LR was more useful at 0.41 (95% CI: 0.36-0.46). Conclusions: A positive screening test for pebbles is not strongly enough associated to be used as a proxy for detecting fentanyl. While the absence of the appearance of pebbles does somewhat reduce the likelihood of fentanyl being present in a given sample, the high prevalence of fentanyl and fentanyl analogues in the drug supply and the risks of consumption are such that public health providers should routinely advise people who use unregulated opioids against solely relying on visual characteristics of drugs as a harm reduction strategy.


Subject(s)
Analgesics, Opioid/chemistry , Fentanyl , Illicit Drugs , Drug Overdose/prevention & control , Fentanyl/chemistry , Harm Reduction , Humans , Illicit Drugs/chemistry
18.
Drug Alcohol Depend ; 218: 108300, 2021 01 01.
Article in English | MEDLINE | ID: mdl-33127185

ABSTRACT

BACKGROUND: Non-prescribed benzodiazepine use is increasing in North America, especially among youth. Owing to increasing demand, counterfeit benzodiazepine tablets are mass-produced in clandestine, unregulated environments and sold as legitimate pharmaceuticals. This study aimed to examine the contents of counterfeit alprazolam tablets available in the unregulated drug market in British Columbia, Canada. METHODS: Data were collected from an ongoing evaluation of a community drug checking service in British Columbia between October 2017 and March 2020. The service operates point-of-care in harm reduction sites using Fourier-transform infrared (FTIR) spectrometers coupled with fentanyl and benzodiazepine immunoassay strips. A subset of samples were sent for confirmatory analysis at partner laboratories and underwent one or more of gas chromatography/mass spectrometry, liquid chromatography/mass spectrometry, and quantitative nuclear magnetic resonance analysis. RESULTS: During the study period, 10,814 total samples were submitted for drug checking, 139 of which were expected to be Xanax (alprazolam) or generic tablets and met the criteria for inclusion. Using FTIR analysis, 33 (23.7 %) samples were identified to contain alprazolam. Only 122 samples were checked using benzodiazepine immunoassay strips and 88 (72.1 %) tested positive. Qualitative results from the 20 samples submitted for confirmatory analysis included various new psychoactive substances and only 2 contained only alprazolam. CONCLUSIONS: Our findings provide evidence that Xanax tablets obtained from the unregulated drug market are likely to be counterfeit and may not contain alprazolam. Drug checking offers people who use drugs a valuable means to determine the contents of their substances; however, limitations of point-of-care technologies must be considered.


Subject(s)
Alprazolam , Counterfeit Drugs , British Columbia , Fentanyl/analysis , Harm Reduction , Humans , Immunoassay/methods , Tablets
19.
Drug Alcohol Rev ; 40(4): 580-585, 2021 05.
Article in English | MEDLINE | ID: mdl-33354869

ABSTRACT

INTRODUCTION: Novel psychoactive substances (NPS) are increasingly being consumed worldwide, with synthetic cannabinoids and synthetic opioids being the second and third most commonly used NPS, respectively. Certain synthetic cannabinoids can produce significant harms, particularly when used with opioids. The objective of this study was to characterise the presence of synthetic cannabinoids in the unregulated drug supply in three Canadian settings METHODS: In the British Columbia setting, all samples were first analysed at point-of-care using combination Fourier-transform infrared (FTIR) spectroscopy and fentanyl immunoassay strips prior to confirmatory testing using quantitative nuclear magnetic resonance spectroscopy, gas chromatography/mass spectrometry (GC/MS) and/or liquid chromatography/mass spectrometry (LC/MS). In the Toronto, Ontario setting, the samples were analysed directly by GC/MS, LC/MS liquid chromatography-high resolution/mass spectrometry. RESULTS: Between January 2018 and December 2019, 38 (2.8%) synthetic cannabinoid samples were detected in the unregulated drug supply (25/909 in British Columbia and 13/440 in Ontario). In British Columbia and Ontario, 76% and 85% of samples, respectively, were expected by individuals to be an opioid. Synthetic cannabinoids detected included AMB-FUBINACA, AB-FUBINACA, 5-fluoro-MDMB-PINACA, and 5-fluoro-MDMB-PICA, and largely co-occurred with fentanyl. In the British Columbia context, Fourier-transform infrared spectroscopy failed to detect synthetic cannabinoid compounds in almost half (48%) of the samples at point-of-care. DISCUSSION AND CONCLUSIONS: As point-of-care technologies failed to detect these compounds in many occasions, our findings demonstrate the importance of laboratory confirmatory analysis to identify NPS. Given the high risk of harm associated with the consumption of synthetic cannabinoids, further research should investigate the reasons for adulteration.


Subject(s)
Cannabinoids , Illicit Drugs , British Columbia , Cannabinoids/adverse effects , Cannabinoids/analysis , Chromatography, Liquid , Drug Contamination , Humans
20.
Drug Alcohol Depend ; 212: 108006, 2020 07 01.
Article in English | MEDLINE | ID: mdl-32438280

ABSTRACT

OBJECTIVES: Point-of-care drug checking services, wherein individuals can check the content and purity of their drugs, have emerged as a public health intervention to address the fentanyl crisis; however, there have been no rigorous evaluations of the technologies against reference standard laboratory techniques. METHODS: Two point-of-care technologies, fentanyl immunoassay strips and Fourier-Transform Infrared (FTIR) spectroscopy, were implemented at two supervised injection sites in Vancouver, Canada. We calculated sensitivity, specificity, and false negative rate for both testing methods as compared to a laboratory reference standard. RESULTS: Between October 2017 and 2018, 331 samples were sent for confirmatory testing. Immunoassay strips had a sensitivity of 87.5% and specificity of 95.2%, with a false negative rate of 12.5%. FTIR spectroscopy had a sensitivity of 72.1% and specificity of 99.0%, with a false negative rate of 27.9%. CONCLUSION: As expected, while FTIR spectroscopy can quantify concentrations on a wide array of compounds, it can only do so above the detection limit. Using FTIR spectroscopy and immunoassay strips in combination has the potential to offset the limitations of each technology when used alone.


Subject(s)
Analgesics, Opioid/standards , Drug Contamination/prevention & control , Fentanyl/standards , Point-of-Care Systems/standards , Analgesics, Opioid/analysis , Canada/epidemiology , Drug Overdose/prevention & control , Fentanyl/analysis , Humans , Immunoassay/methods , Immunoassay/standards , Public Health/methods , Public Health/standards , Spectroscopy, Fourier Transform Infrared/methods , Spectroscopy, Fourier Transform Infrared/standards
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