Online surveillance of novel psychoactive substances (NPS): Monitoring Reddit discussions as a predictor of increased NPS-related exposures

Public health surveillance of new psychoactive substances: recent developments

PURPOSE OF REVIEW

New psychoactive substances (NPS) continue to emerge globally and present a threat to public health. This article summarizes the most recent literature on approaches for monitoring NPS use and adverse events related to use.

RECENT FINDINGS

A variety of approaches have recently been employed for surveillance of NPS use and associated harms, including the use of toxicology testing of patients in emergency departments, surveys of sentinel populations, drug checking and syringe services programs, wastewater-based epidemiology, and retrospective analyses of clinical samples and toxicology reports. These studies cover a range of time periods and NPS examined across numerous countries.

SUMMARY

Areas of particular interest for future research include the use of data from drug checking services to inform surveillance efforts of the illicit drug supply and the development of methods for wastewater-based monitoring of NPS. Studies that combine self-report data with toxicology testing in particular are important for capturing unintentional or unknown exposure to NPS including fentanyls and drugs like xylazine. Given the limitations associated with individual indicators of drug use and associated harms, the harmonization of multiple data sources can help present a more complete picture of both trends involving NPS to better inform public health responses.

Seized drug reporting of NPS helps to guide regional toxicological practice: A 17 month review between 2022 and 2023

Novel psychoactive substances (NPS) are everchanging and plague forensic laboratories who must identify an unending variety of emerging substances and evolve current methodologies to detect these substances. Identifying potential regional NPS targets and timely examining trends in seized drug data could help mitigate the burden laboratories face. Over 17 months, NPS seized drug data were processed and categorized from three laboratories located across the United States to determine any NPS regional similarities and prevalent NPS drug categories: the South Carolina Law Enforcement Division (SLED), the Sedgwick County Regional Forensic Science Center (SCRFSC), and the Orange County Crime Laboratory (OCCL). Seized drug materials, including pills, powders, and plant material, were primarily analyzed for NPS via gas chromatography-mass spectrometry and Fourier transform infrared spectroscopy. From June 2022 to October 2023, 1940 NPS seized drug identifications were reported by these laboratories with 63 different NPS reported. Novel synthetic opioids (NSO) were the most prevalent NPS class across all three laboratories (55%), with fluorofentanyl accounting for 74% of NSO identifications. This is unsurprising given the fentanyl epidemic in the United States. Furthermore, these data highlighted varying regional NPS seized drug trends: eutylone, a synthetic cathinone, was one of the most frequently identified NPS in SLED, SCRFSC observed the most diverse set of synthetic cannabinoids, and OCCL observed an increased prevalence in the designer benzodiazepine, bromazolam. NPS scope recommendations are a valuable resource for forensic laboratories; however, most focus on a national perspective. Timely analysis and reporting of NPS seized drug data may help to develop regional NPS scope recommendations laboratories may employ.

How (Cautious) Social Media Use May Improve Education and Pipeline Efforts of a Growing Postpandemic Forensic Pathologist Workforce Shortage

ABSTRACT

Many subspecialties of pathology have initiated novel methods and strategies to connect with medical students and residents, stimulate interest, and offer mentorship. Emerging concern about the future of forensic pathology has been highlighted in contemporary literature as recruitment of new fellows has stagnated and workforce shortage concerns have blossomed. Amidst these challenges, the potential role of social networking platforms like social media (SoMe) in enhancing autopsy pathology/forensics education has garnered attention, yet literature focusing specifically on its application in autopsy and forensic pathology remains limited. This review aims to provide a comprehensive narrative overview of the current literature on the established uses of SoMe in forensic pathology. It seeks to build upon existing recommendations, introducing a contemporary compilation of online resources designed to facilitate virtual engagement among pathologists, learners, patients, and families. The review supports the idea that strategic, ethical, and conscientious use of SoMe has a place in addressing the growing workforce shortages and closing educational gaps in forensic pathology by enhancing exposure to the field and dispelling antiquated stereotypes.

Synthetic cannabinoids in hair-Prevalence of use in abstinence control programs for driver's license regranting in Germany

Although the use, structural variety, and prevalence of synthetic cannabinoids (SCs) have steadily increased on the drug market, they are rarely analyzed in abstinence control programs for driver's license regranting. The aim of this study was to determine the SC prevalence in these programs by analyzing hair samples collected between March 2020 and March 2021 from various regions in Germany, mainly Bavaria (40%). Specimens were analyzed quantitatively for drugs of abuse and qualitatively for 107 SCs. Hair samples were screened by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and to search for unknown SC analogs, positive samples were additionally screened by liquid chromatography-high resolution time of flight mass spectrometry (LC-qTOF/MS). The analysis of 5097 hair samples resulted in 181 SC detections (3.6%), showing a wide range of 44 SCs, with up to 13 different compounds found in a single sample. The most prevalent compounds were 5F-MDMB-PICA and MDMB-4en-PINACA; furthermore, 10 new substances not initially covered by LC-MS/MS analysis were detected by LC-qTOF/MS. The SC positivity rate was comparable to cocaine (5.4%) and amphetamine (2.6%). Only in 35 cases (0.7%), SC analysis was requested by the clients, highlighting the insufficient coverage of SC consumption in the studied collective. In summary, hair sample analysis proved to be a valuable tool to monitor the use of SCs. In order to keep pace with newly emerging SC analogs, an up-to-date analytical method is essential. Prospectively, SCs should be more routinely screened in hair analysis for abstinence control to avoid cannabis substitution by SCs.

Improving wastewater-based epidemiology for new psychoactive substance surveillance by combining a high-throughput in vitro metabolism assay and LC-HRMS metabolite identification

One of the primary criteria for a suitable drug biomarker for wastewater-based epidemiology (WBE) is having a unique source representing human metabolism. For WBE studies, this means it is important to identify and monitor metabolites rather than parent drugs, to capture consumption of drugs and not fractions that could be directly disposed. In this study, a high-throughput workflow based on a human liver S9 fraction in vitro metabolism assay was developed to identify human transformation products of new chemicals, using α-pyrrolidino-2-phenylacetophenone (α-D2PV) as a case study. Analysis by liquid chromatography coupled to high resolution mass spectrometry identified four metabolites. Subsequently, a targeted liquid chromatography - tandem mass spectrometry method was developed for their analysis in wastewater samples collected from a music festival in Australia. The successful application of this workflow opens the door for future work to better understand the metabolism of chemicals and their detection and application for wastewater-based epidemiology.

Novel Therapeutic and Program-Based Approaches to Opioid Use Disorders

Opioid use disorder continues to drive overdose deaths in many countries, including the United States. Illicit fentanyl and its analogues have emerged as key contributors to the complications and mortality associated with opioid use disorder. Medications for opioid use disorder treatment, such as methadone and buprenorphine, are safe and substantially reduce opioid use, infectious complications, and mortality risk, but remain underutilized. Polysubstance use and emerging substances such as xylazine and designer benzodiazepines create additional treatment challenges. Recent clinical and policy innovations in treatment delivery, including telemedicine, bridge clinics, and expanded models for accessing methadone have the potential to increase access to life-saving care for people living with opioid use disorder.

Trends in Fentanyl Content on Reddit Substance Use Forums, 2013-2021

BACKGROUND

Fentanyl is a pressing concern in the current drug supply. Social media data can provide access to near real-time understanding of drug trends that may complement official mortality data.

DESIGN

The total number of fentanyl-related posts and the total number of posts for eight drug subreddit categories (alcohol, cannabis, hallucinogens, multi-drug, opioids, over the counter, sedatives, stimulants) were collected from 2013 to 2021 using the Pushshift Reddit dataset. The proportion of fentanyl-related posts as a fragment of total subreddit posts was examined. Linear regressions described the rate of change in post volume over time.

RESULTS

Overall, fentanyl-related content increased across drug-related subreddits from 2013 to 2021 (1292% increase, linear trend p ≤ 0.001). Opioid subreddits (30.62 per 1000 posts, linear trend p ≤ 0.001) had the most fentanyl-related content during the examined time period. Multi-drug (5.95 per 1000; p ≤ 0.01), sedative (3.23 per 1000, p ≤ 0.01), and stimulant (1.60 per 1000, p ≤ 0.01) subreddits also had substantial increases in fentanyl-related content. The greatest increases occurred in the multi-drug (1067% 2013:2021) and stimulant (1862% 2014:2021) subreddits.

CONCLUSION

Fentanyl-related posts on Reddit trended upward, with the fastest rate of change for multi-substance and stimulant subreddits. Beyond opioids, harm reduction and public health messaging should ensure inclusion of individuals who use other drugs.

Investigating Substance Use via Reddit: Systematic Scoping Review

BACKGROUND

Reddit's (Reddit Inc) large user base, diverse communities, and anonymity make it a useful platform for substance use research. Despite a growing body of literature on substance use on Reddit, challenges and limitations must be carefully considered. However, no systematic scoping review has been conducted on the use of Reddit as a data source for substance use research.

OBJECTIVE

This review aims to investigate the use of Reddit for studying substance use by examining previous studies' objectives, reasons, limitations, and methods for using Reddit. In addition, we discuss the implications and contributions of previous studies and identify gaps in the literature that require further attention.

METHODS

A total of 7 databases were searched using keyword combinations including Reddit and substance-related keywords in April 2022. The initial search resulted in 456 articles, and 227 articles remained after removing duplicates. All included studies were peer reviewed, empirical, available in full text, and pertinent to Reddit and substance use, and they were all written in English. After screening, 60 articles met the eligibility criteria for the review, with 57 articles identified from the initial database search and 3 from the ancestry search. A codebook was developed, and qualitative content analysis was performed to extract relevant evidence related to the research questions.

RESULTS

The use of Reddit for studying substance use has grown steadily since 2015, with a sharp increase in 2021. The primary objective was to identify tendencies and patterns in various types of substance use discussions (52/60, 87%). Reddit was also used to explore unique user experiences, propose methodologies, investigate user interactions, and develop interventions. A total of 9 reasons for using Reddit to study substance use were identified, such as the platform's anonymity, its widespread popularity, and the explicit topics of subreddits. However, 7 limitations were noted, including the platform's low representativeness of the general population with substance use and the lack of demographic information. Most studies use application programming interfaces for data collection and quantitative approaches for analysis, with few using qualitative approaches. Machine learning algorithms are commonly used for natural language processing tasks. The theoretical, methodological, and practical implications and contributions of the included articles are summarized and discussed. The most prevalent practical implications are investigating prevailing topics in Reddit discussions, providing recommendations for clinical practices and policies, and comparing Reddit discussions on substance use across various sources.

CONCLUSIONS

This systematic scoping review provides an overview of Reddit's use as a data source for substance use research. Although the limitations of Reddit data must be considered, analyzing them can be useful for understanding patterns and user experiences related to substance use. Our review also highlights gaps in the literature and suggests avenues for future research.

Festivals following the easing of COVID-19 restrictions: Prevalence of new psychoactive substances and illicit drugs

The market for illicit drugs and new psychoactive substances (NPS) has grown significantly and people attending festivals have been identified as being at high risk (high extent and frequency of substance use). Traditional public health surveillance data sources have limitations (high costs, long implementation times, and ethical issues) and wastewater-based epidemiology (WBE) can cost-effectively support surveillance efforts. Influent wastewater samples were analyzed for NPS and illicit drug consumption collected during New Year period (from 29-Dec-2021 to 4-Jan-2022) and a summer Festival (from 29-June-2022 to 12-July-2022) in a large city in Spain. Samples were analyzed for phenethylamines, cathinones, opioids, benzodiazepines, plant-based NPS, dissociatives, and the illicit drugs methamphetamine, MDA, MDMA, ketamine, heroin, cocaine, and pseudoephedrine by liquid chromatography mass spectrometry. High consumption rates of specific NPS and established illicit drugs were identified at the peak of each event. Furthermore, a dynamic change in NPS use (presence and absence of substances) was detected over a period of six months. Eleven NPS, including synthetic cathinones, benzodiazepines, plant-based NPS and dissociatives, and seven illicit drugs were found across both the New Year and summer Festival. Statistically significant differences (p < 0.05) were seen for 3-MMC (New Year vs summer Festival), eutylone (New Year vs summer Festival), cocaine (summer Festival vs normal week and summer Festival vs New Year), MDMA (New Year vs normal week and summer Festival vs normal week), heroin (summer Festival vs New Year) and pseudoephedrine (summer Festival vs New Year). This WBE study assessed the prevalence of NPS and illicit drugs at festivals following the reduction of the COVID-19 pandemic restrictions highlighting the high use of specific substances at the peak of each event. This approach identified in a cost-effective and timely manner without any ethical issues the most used drugs and changes in use patterns and, thus, can complement public health information.

No prescription? No problem: A qualitative study investigating self-medication with novel psychoactive substances (NPS)

BACKGROUND

The proliferation of Novel Psychoactive Substances (NPS) presents a challenge for global drug policy. The ease of online drug purchase and the emergence of the dark web have created new avenues for the growth of NPS. Despite the global nature of this issue, limited research has examined motivations of use. These include perceived safety or convenience, an interest in novel pharmacology and self-exploration. Recent evidence has suggested individuals may be self-medicating with NPS, however this phenomenon has yet to be thoroughly explored. This study aims to investigate the occurrence of NPS self-medication, identify the specific NPS involved, and understand the motivations behind their use.

METHODS

Discussions surrounding self-medication using NPS were collected between October 2022 and February 2023 via a content analysis of a Reddit community. Ninety-three threads, comprising 182,490 words and 5023 comments, were collected and cleaned. A frequency analysis was conducted to identify the NPS discussed, and data was analysed systematically through the process of iterative categorization (IC).

RESULTS

Our study revealed frequent discussions about the self-medication with several NPS, notably etizolam, clonazolam, diclazepam, flualprazolam, 2-FMA, 4F-MPH, 3-FPM and 3-MeO-PCP. Individuals were mainly self-treating ADHD, anxiety and depression. Motivations for choosing NPS included access, cost, legality and a dissatisfaction with conventional healthcare. Substances were often chosen based on a profile of "Functionality" and outcomes varied. The use of clonazolam was highlighted as particularly problematic.

CONCLUSION

The current study provides insight into the phenomenon of self-medication with NPS within an internet demographic, exploring the motivations behind why individuals choose NPS for a variety of disorders. The easy access to NPS and lack of scientific data pose a significant challenge for drug policy. Future policies should focus on improving healthcare providers knowledge of NPS use, removing barriers to adult ADHD diagnosis and rebuilding trust between individuals and addiction services.

A Collaborative Platform for Novel Compound Identification - Characterization of Designer Phencyclidines (PCPs) POXP, PTHP, and P2AP

With the sustained prevalence and introduction of new emerging drugs throughout the world there is a need for continued development and maintenance of platforms that enable rapid identification and characterization of unknown compounds. To complement existing efforts, a collaborative platform between the National Institute of Standards and Technology (NIST) and practicing forensic agencies is being deployed which enables laboratories to leverage techniques and expertise that may not exist at their facilities. Using this approach, unknown compounds are identified and characterized using a suite of analytical tools to obtain (1) a rapid preliminary identification followed by (2) a more complete characterization and confirmation of the preliminary identification. To demonstrate this platform, the characterization of three previously unreported analogs of phencyclidine (PCP) - POXP, PTHP, and P2AP - are described. A preliminary identification of the three substances was obtained using direct analysis in real time mass spectrometry (DART-MS) with confirmation by nuclear magnetic resonance (NMR) spectroscopy, gas chromatography mass spectrometry (GC-MS) and gas chromatography flame ionization detection (GC-FID).

Self-reported adverse events associated with ∆8-Tetrahydrocannabinol (Delta-8-THC) Use

BACKGROUND

There is an expanding unregulated market for a psychotropic compound called ∆8-Tetrahydrocannabinol (delta-8-THC) that is being derived from hemp, but a summary of adverse events related to delta-8-THC has not been publicly reported.

METHODS

This case series assessed adverse events reported by delta-8-THC users on the Reddit forum r/Delta8 and compared these to delta-8-THC AEs in the US Food and Drug Administration Adverse Event Reporting System (FAERS). Delta-8-THC and cannabis AEs reported in FAERS were also compared. The r/Delta8 forum was selected because it includes a large sample of 98,700 registered individuals who publicly discuss their experiences using delta-8-THC. All r/Delta8 posts were obtained from August 20, 2020, through September 25, 2022. A random sample of r/Delta8 posts was drawn (n = 10,000) and filtered for posts in which delta-8-THC users reported an adverse event (n = 335). FAERS reports that listed delta-8-THC (N = 326) or cannabis (N = 7076) as a suspect product active ingredient were obtained. Adverse events claimed to result from delta-8-THC use were coded using Medical Dictionary for Regulatory Activities to system organ class and preferred term categories.

RESULTS

The absolute number of delta-8-THC adverse event reports (N = 2184, 95% CI = 1949-2426) and serious adverse event reports (N = 437; 95% CI = 339-541) on r/Delta 8 were higher than the adverse event reports (N = 326) and serious adverse event reports (N = 289) to FAERS. Psychiatric disorders were the most frequently cited system organ class in r/Delta8 adverse event reports, mentioned in 41.2% (95% CI = 35.8%-46.3%) of reports, followed by respiratory, thoracic and mediastinal disorders (29.3%, 95% CI = 25.1%-34.0%) and nervous system disorders (23.3%, 95% CI = 18.5%-27.5%). Anxiety (16.4%, 95% CI = 12.8-20.6), Cough (15.5%, 95% CI = 11.9-20.0) and Paranoia (9.3%, 95% CI = 6.3-12.5) were the most frequently cited preferred terms in adverse event reports. The overall prevalence of AEs reported for cannabis and delta-8-THC on FAERS were also similar when analyzed by system organ class (Pearson's r = 0.88).

CONCLUSIONS

The findings of this case series suggest that most of the adverse events reported by delta-8-THC users are like those reported during acute cannabis intoxication. This finding suggests that health care professionals follow similar treatment and management protocols, and that jurisdictions should clarify whether delta-8-THC can be sold as a hemp product.

Three years of wastewater surveillance for new psychoactive substances from 16 countries

The proliferation of new psychoactive substances (NPS) over recent years has made their surveillance complex. The analysis of raw municipal influent wastewater can allow a broader insight into community consumption patterns of NPS. This study examines data from an international wastewater surveillance program that collected and analysed influent wastewater samples from up to 47 sites in 16 countries between 2019 and 2022. Influent wastewater samples were collected over the New Year period and analysed using validated liquid chromatography - mass spectrometry methods. Over the three years, a total of 18 NPS were found in at least one site. Synthetic cathinones were the most found class followed by phenethylamines and designer benzodiazepines. Furthermore, two ketamine analogues, one plant based NPS (mitragynine) and methiopropamine were also quantified across the three years. This work demonstrates that NPS are used across different continents and countries with the use of some more evident in particular regions. For example, mitragynine has highest mass loads in sites in the United States, while eutylone and 3-methylmethcathinone increased considerably in New Zealand and in several European countries, respectively. Moreover, 2F-deschloroketamine, an analogue of ketamine, has emerged more recently and could be quantified in several sites, including one in China, where it is considered as one of the drugs of most concern. Finally, some NPS were detected in specific regions during the initial sampling campaigns and spread to additional sites by the third campaign. Hence, wastewater surveillance can provide an insight into temporal and spatial trends of NPS use.

Review of the experiences of users of methaqualone and methaqualone derivatives. An analysis of online forums

The aim of this review article was to collect and analyze the available information on methaqualone and its derivatives reported by users in dedicated online forums. Methaqualone is a sedative-hypnotic drug that has been widely used for medical purposes in the past, but is now illegal in most countries due to its high abuse potential. The review collected information on doses, routes of administration, desirable and side effects of intoxication and other relevant aspects of the abuse of these compounds. The results of the study suggest that methaqualone and its derivatives continue to be used by some individuals despite their illicit status and potential health risks. The review, in the absence of other more reliable toxicological data, provides valuable insights from direct users on the use of these substances.

A review of synthetic cathinones emerging in recent years (2019-2022)

Purpose

The emergence of novel psychoactive substances (NPS) has been being a continuous and evolving problem for more than a decade. Every year, dozens of new, previously unknown drugs appear on the illegal market, posing a significant threat to the health and lives of their users. Synthetic cathinones are one of the most numerous and widespread groups among NPS. The purpose of this work was to identify and summarize available data on newly emerging cathinones in very recent years.

Methods

Various online databases such as PubMed, Google Scholar, but also databases of government agencies including those involved in early warning systems, were used in search of reports on the identification of newly emerging synthetic cathinones. In addition, threads on various forums created by users of these drugs were searched for reports on the effects of these new substances.

Results

We have identified 29 synthetic cathinones that have been detected for the first time from early 2019 to mid-2022. We described their structures, known intoxication symptoms, detected concentrations in biological material in poisoning cases, as well as the countries and dates of their first appearance. Due to the lack of studies on the properties of the novel compounds, we compared data on the pharmacological profiles of the better-known synthetic cathinones with available information on the newly emerged ones. Some of these new agents already posed a threat, as the first cases of poisonings, including fatal ones, have been reported.

Conclusions

Most of the newly developed synthetic cathinones can be seen as analogs and replacements for once-popular compounds that have been declining in popularity as a result of legislative efforts. Although it appears that some of the newly emerging cathinones are not widely used, they may become more popular in the future and could become a significant threat to health and life. Therefore, it is important to continue developing early warning systems and identifying new compounds so that their widespread can be prevented.

Proliferation of Novel Synthetic Opioids in Postmortem Investigations After Core-Structure Scheduling for Fentanyl-Related Substances

ABSTRACT

New generations of novel synthetic opioids (NSOs) have emerged to fill a void in the illicit drug markets left by the decline in popularity of fentanyl analogs subsequent to core-structure scheduling of fentanyl-related substances in the United States and China. These new opioids include members of the 2-benzyl benzimidazole (eg, isotonitazene, metonitazene, N -pyrrolidino etonitazene, protonitazene, etodesnitazene), benzimidazolone (eg, brorphine), and cinnamylpiperazine (eg, AP-238, 2-methyl AP-237) subclasses. Novel synthetic opioids continue to be detected in opioid-related fatal overdoses, demonstrating the harms associated with exposure to these drugs. Between January 2020 and December 2021, 384 casework blood samples were reported by our laboratory to contain 1 or more of the prior listed 8 NSOs. Isotonitazene (n = 144), metonitazene (n = 122), and brorphine (n = 91) were the 3 most prevalent substances, with positivity for isotonitazene and brorphine peaking just before the announcement of emergency scheduling. These NSOs have been documented as significant drivers of drug mortality, and this case series described here highlights the challenges medical examiners and coroners face in staying current with emerging drugs. Challenges include regional differences, rapid turnover, short lifecycles, variable toxicology testing, and difficulty in assessing individual drug toxicity in polydrug cases.

Retrospective identification of new psychoactive substances in patient samples submitted for clinical drug analysis

New psychoactive substances (NPS) are life-threatening through unpredictable toxicity and limited analytical options for clinicians. We present the retrospective identification of NPS in raw data from a liquid chromatography-high resolution mass spectrometry (LC-HRMS) based multidrug panel analysis on 14,367 clinical oral fluid samples requested during 2019 mainly by psychiatric and addiction care clinics. Retrospectively analysed NPS included 48 notified originally in 2019 by the European Union Early Warning System (EU-EWS) and 28 frequently reported in Sweden. Of 88 included NPS, 34 (mitragynine, flualprazolam, 3F/4F-α-P(i)HP, etizolam, 4F-MDMB-BINACA, cyproheptadine, 5F-MDMB-PICA, isotonitazene, isohexedrone, MDPEP, N-ethylpentedrone, tianeptine, flubromazolam, 4'-methylhexedrone, α-P(i)HP, eutylone, mephedrone, N-ethylhexedrone, 5F-MDMB-PINACA, ADB-BUTINACA, 3-methoxy PCP, 4F-furanylfentanyl, 4F-isobuturylfentanyl, acrylfentanyl, furanylfentanyl, clonazolam, norfludiazepam, 3F-phenmetrazine, 3-MMC, 4-methylpentedrone, BMDP, ethylphenidate, methylone, α-PVP) were identified as 219 findings in 84 patients. Eight NPS notified in 2019 were identified, five before EWS release. NPS occurred in 1.20% of all samples and 1.53% of samples containing traditional drugs, and in 1.87% of all patients and 2.88% of patients using traditional drugs. NPS use was more common in men and polydrug users. Legal (not scheduled) NPS were more used than comparable illegal ones. Retrospective identification could be useful when prioritizing NPS for clinical routine analysis and when studying NPS epidemiology.

Signals of increasing co-use of stimulants and opioids from online drug forum data

Background

Despite recent rises in fatal overdoses involving multiple substances, there is a paucity of knowledge about stimulant co-use patterns among people who use opioids (PWUO) or people being treated with medications for opioid use disorder (PTMOUD). A better understanding of the timing and patterns in stimulant co-use among PWUO based on mentions of these substances on social media can help inform prevention programs, policy, and future research directions. This study examines stimulant co-mention trends among PWUO/PTMOUD on social media over multiple years.

Methods

We collected publicly available data from 14 forums on Reddit (subreddits) that focused on prescription and illicit opioids, and medications for opioid use disorder (MOUD). Collected data ranged from 2011 to 2020, and we also collected timelines comprising past posts from a sample of Reddit users (Redditors) on these forums. We applied natural language processing to generate lexical variants of all included prescription and illicit opioids and stimulants and detect mentions of them on the chosen subreddits. Finally, we analyzed and described trends and patterns in co-mentions.

Results

Posts collected for 13,812 Redditors showed that 12,306 (89.1%) mentioned at least 1 opioid, opioid-related medication, or stimulant. Analyses revealed that the number and proportion of Redditors mentioning both opioids and/or opioid-related medications and stimulants steadily increased over time. Relative rates of co-mentions by the same Redditor of heroin and methamphetamine, the substances most commonly co-mentioned, decreased in recent years, while co-mentions of both fentanyl and MOUD with methamphetamine increased.

Conclusion

Our analyses reflect increasing mentions of stimulants, particularly methamphetamine, among PWUO/PTMOUD, which closely resembles the growth in overdose deaths involving both opioids and stimulants. These findings are consistent with recent reports suggesting increasing stimulant use among people receiving treatment for opioid use disorder. These data offer insights on emerging trends in the overdose epidemic and underscore the importance of scaling efforts to address co-occurring opioid and stimulant use including harm reduction and comprehensive healthcare access spanning mental-health services and substance use disorder treatment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12954-022-00628-2.