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Concept: Opioids


In March and October 2015, the Drug Enforcement Administration (DEA) and CDC, respectively, issued nationwide alerts identifying illicitly manufactured fentanyl (IMF) as a threat to public health and safety (1,2). IMF is unlawfully produced fentanyl, obtained through illicit drug markets, includes fentanyl analogs, and is commonly mixed with or sold as heroin (1,3,4). Starting in 2013, the production and distribution of IMF increased to unprecedented levels, fueled by increases in the global supply, processing, and distribution of fentanyl and fentanyl-precursor chemicals by criminal organizations (3). Fentanyl is a synthetic opioid 50-100 times more potent than morphine (2).* Multiple states have reported increases in fentanyl-involved overdose (poisoning) deaths (fentanyl deaths) (2). This report examined the number of drug products obtained by law enforcement that tested positive for fentanyl (fentanyl submissions) and synthetic opioid-involved deaths other than methadone (synthetic opioid deaths), which include fentanyl deaths and deaths involving other synthetic opioids (e.g., tramadol). Fentanyl deaths are not reported separately in national data. Analyses also were conducted on data from 27 states(†) with consistent death certificate reporting of the drugs involved in overdoses. Nationally, the number of fentanyl submissions and synthetic opioid deaths increased by 426% and 79%, respectively, during 2013-2014; among the 27 analyzed states, fentanyl submission increases were strongly correlated with increases in synthetic opioid deaths. Changes in fentanyl submissions and synthetic opioid deaths were not correlated with changes in fentanyl prescribing rates, and increases in fentanyl submissions and synthetic opioid deaths were primarily concentrated in eight states (high-burden states). Reports from six of the eight high-burden states indicated that fentanyl-involved overdose deaths were primarily driving increases in synthetic opioid deaths. Increases in synthetic opioid deaths among high-burden states disproportionately involved persons aged 15-44 years and males, a pattern consistent with previously documented IMF-involved deaths (5). These findings, combined with the approximate doubling in fentanyl submissions during 2014-2015 (from 5,343 to 13,882) (6), underscore the urgent need for a collaborative public health and law enforcement response.

Concepts: Drug, Opioid, Morphine, Drug addiction, Heroin, Naloxone, Opioids, Drug Enforcement Administration


Objective To compare the risk for all cause and overdose mortality in people with opioid dependence during and after substitution treatment with methadone or buprenorphine and to characterise trends in risk of mortality after initiation and cessation of treatment.Design Systematic review and meta-analysis.Data sources Medline, Embase, PsycINFO, and LILACS to September 2016.Study selection Prospective or retrospective cohort studies in people with opioid dependence that reported deaths from all causes or overdose during follow-up periods in and out of opioid substitution treatment with methadone or buprenorphine.Data extraction and synthesis Two independent reviewers performed data extraction and assessed study quality. Mortality rates in and out of treatment were jointly combined across methadone or buprenorphine cohorts by using multivariate random effects meta-analysis.Results There were 19 eligible cohorts, following 122 885 people treated with methadone over 1.3-13.9 years and 15 831 people treated with buprenorphine over 1.1-4.5 years. Pooled all cause mortality rates were 11.3 and 36.1 per 1000 person years in and out of methadone treatment (unadjusted out-to-in rate ratio 3.20, 95% confidence interval 2.65 to 3.86) and reduced to 4.3 and 9.5 in and out of buprenorphine treatment (2.20, 1.34 to 3.61). In pooled trend analysis, all cause mortality dropped sharply over the first four weeks of methadone treatment and decreased gradually two weeks after leaving treatment. All cause mortality remained stable during induction and remaining time on buprenorphine treatment. Overdose mortality evolved similarly, with pooled overdose mortality rates of 2.6 and 12.7 per 1000 person years in and out of methadone treatment (unadjusted out-to-in rate ratio 4.80, 2.90 to 7.96) and 1.4 and 4.6 in and out of buprenorphine treatment.Conclusions Retention in methadone and buprenorphine treatment is associated with substantial reductions in the risk for all cause and overdose mortality in people dependent on opioids. The induction phase onto methadone treatment and the time immediately after leaving treatment with both drugs are periods of particularly increased mortality risk, which should be dealt with by both public health and clinical strategies to mitigate such risk. These findings are potentially important, but further research must be conducted to properly account for potential confounding and selection bias in comparisons of mortality risk between opioid substitution treatments, as well as throughout periods in and out of each treatment.

Concepts: Cohort study, Opioid, Morphine, Naloxone, Analgesic, Buprenorphine, Methadone, Opioids


Preliminary estimates of U.S. drug overdose deaths exceeded 60,000 in 2016 and were partially driven by a fivefold increase in overdose deaths involving synthetic opioids (excluding methadone), from 3,105 in 2013 to approximately 20,000 in 2016 (1,2). Illicitly manufactured fentanyl, a synthetic opioid 50-100 times more potent than morphine, is primarily responsible for this rapid increase (3,4). In addition, fentanyl analogs such as acetylfentanyl, furanylfentanyl, and carfentanil are being detected increasingly in overdose deaths (5,6) and the illicit opioid drug supply (7). Carfentanil is estimated to be 10,000 times more potent than morphine (8). Estimates of the potency of acetylfentanyl and furanylfentanyl vary but suggest that they are less potent than fentanyl (9). Estimates of relative potency have some uncertainty because illicit fentanyl analog potency has not been evaluated in humans. This report describes opioid overdose deaths during July-December 2016 that tested positive for fentanyl, fentanyl analogs, or U-47700, an illicit synthetic opioid, in 10 states participating in CDC’s Enhanced State Opioid Overdose Surveillance (ESOOS) program.* Fentanyl analogs are similar in chemical structure to fentanyl but not routinely detected because specialized toxicology testing is required. Fentanyl was detected in at least half of opioid overdose deaths in seven of 10 states, and 57% of fentanyl-involved deaths also tested positive for other illicit drugs, such as heroin. Fentanyl analogs were present in >10% of opioid overdose deaths in four states, with carfentanil, furanylfentanyl, and acetylfentanyl identified most frequently. Expanded surveillance for opioid overdoses, including testing for fentanyl and fentanyl analogs, assists in tracking the rapidly changing illicit opioid market and informing innovative interventions designed to reduce opioid overdose deaths.

Concepts: Drug, Opioid, Morphine, Drug addiction, Heroin, Naloxone, Opioids, Drug overdose


Deaths from prescription-opioid overdose have increased dramatically in the United States, quadrupling in the past 15 years. Efforts to improve pain management resulted in quadrupled rates of opioid prescribing, which propelled a tightly correlated epidemic of addiction, overdose, and death from prescription opioids that is now further evolving to include increasing use and overdoses of heroin and illicitly produced fentanyl. The pendulum of opioid use in pain management has swung back and forth several times over the past 100 years. Beginning in the 1990s, efforts to improve treatment of pain failed to adequately take into account opioids' addictiveness, low therapeutic . . .

Concepts: United States, Opioid, Pain, Morphine, Drug addiction, Heroin, Naloxone, Opioids


The opioid use and overdose crisis is persistent and dynamic. Opioid overdoses were initially driven in the 1990s and 2000s by the increasing availability and misuse of prescription opioids. More recently, opioid overdoses are increasing at alarming rates due to wider use of heroin, which in some places is mixed with fentanyl or fentanyl derivatives. Naloxone access for opioid overdose rescue is one of the US Department of Health and Human Services' three priority areas for responding to the opioid crisis. This article summarizes the known benefits of naloxone access and details unanswered questions about overdose education and naloxone rescue kits. Hopefully future research will address these knowledge gaps, improve the effectiveness of opioid overdose education and naloxone distribution programs, and unlock the full promise of naloxone rescue kits.

Concepts: Opioid, Morphine, Heroin, Naloxone, Opioids, Drug overdose, Opioid overdose


: Novel synthetic opioids (NSOs) include various analogs of fentanyl and newly emerging non-fentanyl compounds. Together with illicitly manufactured fentanyl (IMF), these drugs have caused a recent spike in overdose deaths, whereas deaths from prescription opioids have stabilized. NSOs are used as stand-alone products, as adulterants in heroin, or as constituents of counterfeit prescription medications. During 2015 alone, there were 9580 deaths from synthetic opioids other than methadone. Most of these fatalities were associated with IMF rather than diverted pharmaceutical fentanyl. In opioid overdose cases, where the presence of fentanyl analogs was examined, analogs were implicated in 17% of fatalities. Recent data from law enforcement sources show increasing confiscation of acetylfentanyl, butyrylfentanyl, and furanylfentanyl, in addition to non-fentanyl compounds such as U-47700. Since 2013, deaths from NSOs in the United States were 52 for acetylfentanyl, 40 for butyrylfentanyl, 128 for furanylfentanyl, and 46 for U-47700. All of these substances induce a classic opioid toxidrome, which can be reversed with the competitive antagonist naloxone. However, due to the putative high potency of NSOs and their growing prevalence, it is recommended to forgo the 0.4 mg initial dose of naloxone and start with 2 mg. Because NSOs offer enormous profit potential, and there is strong demand for their use, these drugs are being trafficked by organized crime. NSOs present major challenges for medical professionals, law enforcement agencies, and policymakers. Resources must be distributed equitably to enhance harm reduction though public education, medication-assisted therapies, and improved access to naloxone.This is an open access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.

Concepts: Pharmacology, Opioid, Morphine, Heroin, Naloxone, Buprenorphine, Opioids, Law enforcement agency


Pruritus is a distressing hallmark of the uremic condition, affecting approximately 60% of hemodialysis patients. Abnormal endogenous opioid ligand activity at μ and κ-opioid receptors has been postulated as a mechanism in uremic pruritus. Nalbuphine is a μ-opioid antagonist and κ-opioid agonist.

Concepts: Receptor, Opioid, Receptor antagonist, Opioid receptor, Inverse agonist, Buprenorphine, Opioids, Nalbuphine


The US is experiencing an unprecedented opioid overdose epidemic fostered in recent years by regional contamination of the heroin supply with the fentanyl family of synthetic opioids. Since 2011 opioid-related overdose deaths in the East Coast state of Massachusetts have more than tripled, with 75% of the 1374 deaths with an available toxicology positive for fentanyl. Fentanyl is 30-50X more potent than heroin and its presence makes heroin use more unpredictable. A rapid ethnographic assessment was undertaken to understand the perceptions and experiences of people who inject drugs sold as ‘heroin’ and to observe the drugs and their use.

Concepts: United States, Opioid, Morphine, Drug addiction, Heroin, Naloxone, Hydromorphone, Opioids


As physicians have increased opioid prescribing, overdose deaths from pharmaceutical opioids have substantially increased in the United States. Naloxone hydrochloride (naloxone), an opioid antagonist, is the standard of care for treatment of opioid induced respiratory depression. Since 1996, community-based programs have offered overdose prevention education and distributed naloxone for bystander administration to people who use opioids, particularly heroin. There is growing interest in translating overdose education and naloxone distribution (OEND) into conventional medical settings for patients who are prescribed pharmaceutical opioids. For this review, we summarized and classified existing publications on overdose education and naloxone distribution to identify evidence of effectiveness and opportunities for translation into conventional medical settings.

Concepts: Opioid, Morphine, Opioid receptor, Heroin, Naloxone, Buprenorphine, Opioids, Drug overdose


One-third of cancer patients require opioid rotation (OR) to treat uncontrolled pain or opioid-induced neurotoxicity. Although fentanyl is the most frequently rotated opioid in cancer patients, the accurate opioid rotation ratio (ORR) from transdermal fentanyl (TDF) to other so-called “strong” opioids is unknown.

Concepts: Opioid, Pain, Morphine, Heroin, Buprenorphine, Fentanyl, Pethidine, Opioids