Comparison of fatal poisonings by prescription opioids

Evidence for peripheral and central actions of codeine to dysregulate swallowing in the anesthetized cat

Systemic administration of opioids has been associated with aspiration and swallow dysfunction in humans. We speculated that systemic administration of codeine would induce dysfunctional swallowing and that this effect would have a peripheral component. Experiments were conducted in spontaneously breathing, anesthetized cats. The animals were tracheotomized and electromyogram (EMG) electrodes were placed in upper airway and chest wall respiratory muscles for recording swallow related motor activity. The animals were allocated into three groups: vagal intact (VI), cervical vagotomy (CVx), and supra-nodose ganglion vagotomy (SNGx). A dose response to intravenous codeine was performed in each animal. Swallowing was elicited by injection of 3 mL of water into the oropharynx. The number of swallows after vehicle was significantly higher in the VI group than in SNGx. Codeine had no significant effect on the number of swallows induced by water in any of the groups. However, the magnitudes of water swallow-related EMGs of the thyropharyngeus muscle were significantly increased in the VI and CVx groups by 2-4 fold in a dose-related manner. In the CVx group, the geniohyoid muscle EMG during water swallows was significantly increased. There was a significant dose-related increase in spontaneous swallowing in each group from codeine. The spontaneous swallow number at the 10 mg/kg dose of codeine was significantly larger in the CVx group than that in the SNGx group. During water-evoked swallows, intravenous codeine increased upper airway motor drive in a dose-related manner, consistent with dysregulation. The data support the existence of both central and peripheral actions of codeine on spontaneous swallowing. At the highest dose of codeine, the reduced spontaneous swallow number in the SNGx group relative to CVx is consistent with a peripheral excitatory action of codeine either on pharyngeal/laryngeal receptors or in the nodose ganglion itself. The higher number of swallows in the CVx group than the VI group supports disinhibition of this behavior by elimination of inhibitory vagal sensory afferents.

Heroin metabolism in human blood and its impact for the design of an immunotherapeutic approach against heroin effects

Immunotherapeutic interventions that block drug effects by binding drug molecules to specific antibodies in the bloodstream have shown promising effects in animal studies. For heroin, which effects are mainly mediated by the metabolites 6-acetylmorphine (6-AM; also known as 6-monoacetylmorphine or 6-MAM) and morphine, the optimal antibody specificity has been discussed. In rodents, 6-AM specific antibodies have been recommended based on the rapid metabolism of heroin to 6-AM in the bloodstream. Since the metabolic rate of heroin in blood is unsettled in humans, we examined heroin metabolism with state-of-the-art analytical methodology (UHPLC-MS/MS) in freshly drawn human whole blood incubated with a wide range of heroin concentrations (1-500 μM). The half-life of heroin was highly concentration dependent, ranging from 1.2-1.7 min for concentrations at or above 25 μM, and gradually increasing to approximately 20 min for 1 μM heroin. At concentrations that can be attained in the bloodstream shortly after an i.v. injection, approximately 70% was transformed into 6-AM within 3 min, similar to previous observations in vivo. Our results indicate that blood enzymes play a more important role for the rapid metabolism of heroin in humans than previously assumed. This points to 6-AM as an important target for an efficient immunotherapeutic approach to block heroin effects in humans.

Rapid and sensitive SERS detection of opioids in solutions based on the solid chip Au-coated Si nano-cone array

Rapid and flexible detection or accurate recognition of trace drugs is of great importance in cracking down on drug crimes, but it remains to be expected. Here, a solid chip is presented for the efficient detection and recognition of trace opioids (typically morphine) in aqueous solutions based on surface-enhanced Raman spectroscopy (SERS). Firstly, a Au-coated Si nano-cone array (Au-SNCA) is designed and fabricated via Si-based organic colloidal template etching and Au deposition. This Au-SNCA shows three-dimensional nanostructure with high densities of nanotips and deep nanogaps as well as high structural consistency, which exhibits strong SERS activity to morphine and outstanding stability. Then, such Au-SNCA is used as solid SERS chip to detect morphine in aqueous solutions. It has been demonstrated that using such solid chip, trace morphine in solutions could be recognized and detected within 1 min, and the detection limit is 10^-5 mg/mL (∼10 ppb), showing rapid and sensitive detection, which is much better than the previous reports. Meanwhile, the Au-SNCA chip also can be utilized to detect trace morphine in tap water and reservoir water, the recoveries range from 90.4% to 102.4%. Such excellent SERS performance of this Au-SNCA chip is attributed to its special structure which enhances not only local electromagnetic field but also molecular adsorption. The experimental results about the effects of immersion time and concentration show that the adsorption behavior of morphine molecules on such Au-SNCA chip can be explained by the pseudo-second-order kinetic model and Freundlich adsorption mode. Moreover, the Au-SNCA chip is also suitable for the identification of morphine homologues and the broad-spectrum detection of various common drugs. This study presents a practical solid chip and a simple approach for the efficient SERS detection and recognition of trace drugs in solutions. This is of significance to on-site detect drugs in forensic science.

Short-term mortality following tramadol poisonings in Denmark

Tramadol is a commonly used opioid with a potential of addiction and abuse. Using Danish nationwide registers, we aimed to (1) characterise opioid poisonings; (2) assess the 30-day mortality following morphine, oxycodone, and mixed poisonings compared to tramadol poisonings; and (3) assess the development in tramadol poisonings during a 12-year period. Poisonings were identified from 2006 to 2017. A Cox proportional hazards regression model was used to estimate adjusted hazard ratios (aHRs) along with 95% confidence intervals (CIs) for 30-day mortality following morphine, oxycodone or mixed poisonings compared to tramadol poisonings. We identified 7718 opioid poisonings among 6365 patients. The patients with a tramadol poisoning were younger and had less comorbidities than the patients with a morphine, oxycodone or mixed poisoning. Within 30 days, a total of 205 patients died. The 30-day mortality risk was higher following morphine (aHR 3.2, 95% CI 2.0-5.1), oxycodone (aHR 2.1, 95% CI 1.2-3.6) and mixed poisonings (aHR 1.6, 95% CI 1.0-2.7) compared to tramadol poisonings. The annual number of tramadol poisonings increased from 233 in 2006 to 501 in 2013 and declined to 348 in 2017. In conclusion, despite a lower mortality risk compared to other opioid poisonings, physicians should consider the poisoning and abuse risks when prescribing tramadol.

Health harms of non-medical prescription opioid use: A systematic review

ISSUES

Non-medical prescription opioid use (NMPOU) contributes substantially to the global burden of morbidity. However, no systematic assessment of the scientific literature on the associations between NMPOU and health outcomes has yet been undertaken.

APPROACH

We undertook a systematic review evaluating health outcomes related to NMPOU based on ICD-10 clinical domains. We searched 13 electronic databases for original research articles until 1 July 2021. We employed an adaptation of the Oxford Centre for Evidence-Based Medicine 'Levels of Evidence' scale to assess study quality.

KEY FINDINGS

Overall, 182 studies were included. The evidence base was largest on the association between NMPOU and mental and behavioural disorders; 71% (129) studies reported on these outcomes. Less evidence exists on the association of NMPOU with infectious disease outcomes (26; 14%), and on external causes of morbidity and mortality, with 13 (7%) studies assessing its association with intentional self-harm and 1 study assessing its association with assault (<1%).

IMPLICATIONS

A large body of evidence has identified associations between NMPOU and opioid use disorder as well as on fatal and non-fatal overdose. We found equivocal evidence on the association between NMPOU and the acquisition of HIV, hepatitis C and other infectious diseases. We identified weak evidence regarding the potential association between NMPOU and intentional self-harm, suicidal ideation and assault.

DISCUSSION AND CONCLUSIONS

Findings may inform the prevention of harms associated with NMPOU, although higher-quality research is needed to characterise the association between NMPOU and the full spectrum of physical and mental health disorders.

Survival Impact of Long-Term Tramadol Use on Breast Cancer for Patients with Chronic Pain: A Propensity Score-Matched Population-Based Cohort Study

Purpose: The impact of tramadol analgesic use before breast cancer diagnosis on survival in patients with chronic pain is unclear. Therefore, we designed a propensity score-matched population-based cohort study to compare the breast cancer-related survival of patients with chronic pain who received long-term tramadol analgesic treatment with that of those who did not receive such treatment. Patients and Methods: We included patients with chronic pain and categorized them into two groups according to their analgesic use, comparing their breast cancer-related survival; patients with breast cancer and chronic pain who were prescribed ≥180 defined daily doses (DDDs) of tramadol analgesics per year >3 months before breast cancer diagnosis comprised the case group, and those who were prescribed non-tramadol analgesics before breast cancer diagnosis comprised the control group. Patients in both groups were matched at a ratio of 1:5. Results: The matching process yielded a final cohort of 624 patients (104 and 520 in the case and control groups, respectively) who were eligible for further analysis. According to both univariate and multivariate Cox regression analyses, the adjusted hazard ratio for all-cause death in the case group compared with in the control group was 3.45 (95% confidence interval = 2.36−5.04; p < 0.001). Conclusion: Long-term tramadol analgesic use prior to breast cancer diagnosis might be associated with poor overall survival in patients with chronic pain compared with such patients that did not receive long-term tramadol analgesic treatment.

Effect of Methadone and Tramadol Opioids on Stem Cells Based on Integrated Plasmonic-Ellipsometry Technique

Introduction: Plasmonic biosensors provide high sensitivity in detecting the low amount of biomarkers and pharmaceutical drugs. We studied the mesenchyme cell activity under the treatment of common sedative drugs of methadone and tramadol using the integrated plasmonic-ellipsometry technique. Methods: Mesenchymal stem cells were cultured on patterned plasmonic chips under the treatment of methadone and tramadol drugs. Three cultured chips were kept non-treated as the control ones. The plasmonic-ellipsometry technique was applied to study the signaling characteristic of the cells affected by these two drugs. In this technique, optical information regarding the amplitude ratio and phase change between p- and s-polarized light was recorded. Results: This drug treatment could affect the spectral plasmonic resonance and subsequently the phase shift (Δ) and the amplitude ratio (Ψ) values under p- and s-polarized impinging light. A more significant Δ value for tramadol treatment meant that the phase split was larger between p- and s-polarized light. Tramadol also had more prominent absolute Δ eff and Ψ eff values in comparison with methadone. Conclusion: We showed that tramadol caused more contrast in phase shift (Δ) and amplitude ratio (Ψ) between p- and s-polarized impinging light for cultured stem cells in comparison with methadone. It means that tramadol differentiated more the optical responses for p- and s-polarized lights compared to methadone. Our proposed technique possesses the potential of quantitative and qualitative analysis of drugs on humans even on a cell scale.

Summary statistics for drugs and alcohol concentration recovered in post-mortem femoral blood in Western Switzerland

In post-mortem investigations of fatal intoxication, it is challenging to determine which drug(s) were responsible for the death, and which drugs did not. This study aims to provide post-mortem femoral blood drug levels in lethal intoxication and in post-mortem control cases, where the cause of death was other than intoxication. The reference values could assist in the interpretation of toxicological results in the routine casework. To this end, all post-mortem toxicological results in femoral blood from 2011 to 2017 in Western Switzerland were considered. A full autopsy with systematic toxicological analysis (STA) was conducted in all cases. Results take into account the cause of death classified into one of four categories (as published by Druid and colleagues): I) certified intoxication by one substance alone, IIa) certified intoxication by more than one substance, IIb) certified other causes of death with incapacitation due to drugs, and III) certified other causes of death without incapacitation due to drugs. This study includes 1 990 post-mortem cases where femoral blood was analysed. The material comprised 619 women (31%) and 1 371 men (69%) with a median age of 50 years. The concentrations of the 32 most frequently recorded substances as well as alcohol are discussed. These include 6 opioids and opiates, 3 antidepressants, 6 neuroleptics and hypnotics, 1 barbiturate, 11 benzodiazepines (and related drugs), 2 amphetamine-type stimulants, cocaine, paracetamol, and tetrahydrocannabinol (THC). The most common substances that caused intoxication alone were morphine, methadone, ethanol, tramadol, and cocaine. The post-mortem concentration ranges for all substance are categorized as I, IIa, IIb, or III. Statistical post-mortem reference concentrations for drugs are discussed and compared with previously published concentrations. This study shows that recording and classifying cases is time-consuming, but it is rewarding in a long-term perspective to achieve a more reliable information about fatal and non-fatal blood concentrations.

A review on tramadol toxicity: mechanism of action, clinical presentation, and treatment

Aims

As an analgesic that acts upon the central nervous system (CNS), tramadol has gained popularity in treating moderate to severe pain. Recently, it has been increasingly reported as a drug of misuse with intentional overdoses or intoxications. This review focuses on tramadol intoxication in humans and its effects on different systems.

Subject and method

This narrative review provides a comprehensive view of the pharmacokinetics, mechanism of action, and incidence of tramadol toxicity with an in-depth look at its side effects. In addition, the main approaches to the management of tramadol poisoning are described.

Results

Tramadol poisoning can affect multiple organ systems: gastrointestinal, central nervous system (seizure, CNS depression, low-grade coma, anxiety, and over time anoxic brain damage), cardiovascular system (palpitation, mild hypertension to life-threatening complications such as cardiopulmonary arrest), respiratory system, renal system (renal failure with higher doses of tramadol intoxication), musculoskeletal system (rhabdomyolysis), endocrine system (hypoglycemia), as well as, cause serotonin syndrome. Seizure, a serious nervous disturbance, is more common in tramadol intoxication than with other opioids. Fatal tramadol intoxications are uncommon, except in ingestion cases concurrent with other medications, particularly CNS depressants, most commonly benzodiazepines, and ethanol.

Conclusion

With the increasing popularity of tramadol, physicians must be aware of its adverse effects, substantial abuse potential, and drug interactions, to weigh its risk–benefit ratio for pain management. Alternative therapies might be considered in patients with a previous overdose history to reduce risks for adverse outcomes.

The Role of Risk or Contributory Death Factors in Methadone-Related Fatalities: A Review and Pooled Analysis

Methadone-related deaths are characterized by a wide range of post-mortem blood concentrations, due to the high pharmacokinetic/dynamic inter-individual variability, the potential subjective tolerance state and to other risk factors or comorbidities, which might enhance methadone acute toxicity. In the present study, the association among pre-existing and external conditions and diseases and the resultant methadone death capacity have been investigated. Beside a systematic literature review, a retrospective case-control study was done, dividing cases in which methadone was the only cause of death (controls), and those with associated clinical-circumstantial (naive/non-tolerant state), pathological (pulmonary or cardiovascular diseases) or toxicological (other drugs detected) conditions. Methadone concentrations were compared between the two groups and the association with conditions/diseases was assessed by multiple linear and binomial logistic regressions. Literature cases were 139, in house 35, consisting of 22 controls and 152 cases with associated conditions/diseases. Mean methadone concentrations were 2122 ng/mL and 715 ng/mL in controls and cases respectively, with a statistically significant difference (p < 0.05). Lower methadone concentrations (by 24, 19 and 33% respectively) were detected in association with naive/non-tolerant state, pulmonary diseases and presence of other drugs, and low levels of methadone (<600 ng/mL) might lead to death in the presence of the above conditions/diseases.

Impact of a physician-targeted letter on opioid prescribing

We study the effect of a physician-targeted nudge letter on opioid prescribing. In May 2017, the Social Insurance Institution of Finland sent a personal information letter to all physicians who had issued a prescription containing at least 100 tablets of paracetamol-codeine combination to a new patient. The aim of the letter was to draw the physicians' attention to their prescribing practices and to decrease the size of the first codeine prescription. Using individual level register data and a difference-in-differences strategy, we estimate that the letter decreased the average number of tablets purchased by new patients by 12.5 percent and the probability of a first purchase being at least 100 tablets by six percentage points. We also find that these effects were larger among consistent high prescribers. However, we do not find similar effects on other mild or strong opioids.

Comparing rates and characteristics of ambulance attendances related to extramedical use of pharmaceutical opioids in Victoria, Australia from 2013 to 2018

BACKGROUND AND AIMS

Despite increases in opioid prescribing and related morbidity and mortality, few studies have comprehensively documented harms across opioid types. We examined a population-wide indicator of extramedical pharmaceutical opioid-related harm to determine if the supply-adjusted rates of ambulance presentations, the severity of presentations or other attendance characteristics differed by opioid type.

DESIGN

Retrospective observational study of coded ambulance patient care records related to extramedical pharmaceutical opioid use, January 2013 to September 2018.

SETTING

Australia CASES: Primary analyses used Victorian data (n = 9823), with available data from other Australian jurisdictions (n = 4338) used to determine generalizability.

MEASUREMENTS

We calculated supply-adjusted rates of attendances using Poisson regression, and used multinomial logistic regression to compare demographic, presentation severity, mental health, substance use and other characteristics of attendances associated with seven pharmaceutical opioids.

FINDINGS

In Victoria, the highest rates of attendance [per 100 000 oral morphine equivalent mg (OME)] were for codeine (0.273/100 000) and oxycodone (0.113/100 000). The lowest rates were for fentanyl (0.019/100 000) and tapentadol (0.005/100 000). Oxycodone-naloxone rates (0.031/100 000) were lower than for oxycodone as a single ingredient (0.113/100 000). Fentanyl-related attendances were associated with the most severe characteristics, most likely to be an accidental overdose, most likely to have naloxone administered and least likely to be transferred to hospital. In contrast, codeine-related attendances were more likely to involve suicidal thoughts/behaviours, younger females and be transported to hospital. Supply-adjusted attendance rates for individual opioids were stable over time. Victorian states were broadly consistent with non-Victorian states.

CONCLUSIONS

In Australia, rates and characteristics of opioid-related harm vary by opioid type. Supply-adjusted ambulance attendance rates appear to be both stable over time and unaffected by large changes in supply.

Impact of Pharmacological Treatments for Opioid Use Disorder on Mortality

The use of pharmacological treatments for opioid use disorders, including methadone, buprenorphine and naltrexone has been associated with a reduction in mortality compared with illicit opioid use. However, these treatments can also contribute significantly to the risk of death. The opioid agonists methadone and buprenorphine achieve clinical efficacy in patients with an opioid use disorder through suppressing craving and diminishing the effectiveness of illicit opioid doses, while the antagonist naltrexone blocks the action of opioids. Pharmacological differences between opioid pharmacotherapies then create different temporal patterns of protection and mortality risk, different risks of relapse to illicit opioid use, and variations in direct and indirect toxicity, which are revealed in clinical and epidemiological studies. Induction onto methadone and the cessation of oral naltrexone treatment are associated with an elevated risk of opioid poisoning, which is not apparent in patients treated with buprenorphine or sustained-release naltrexone. Beyond drug-related mortality, these pharmacotherapies can impact a participant's risk of death. Buprenorphine may also have some advantages over methadone in patients with depressive disorders or cardiovascular abnormalities. Naltrexone, which is also commonly prescribed to manage problem alcohol use, may reduce deaths in chronic co-alcohol users. Understanding these pharmacologically driven patterns then guides the judicious choice of drug and dosing schedule and the proactive risk management that is crucial to minimising the risk of death in treatment.

Quantifying enhanced risk from alcohol and other factors in polysubstance-related deaths

BACKGROUND

To quantify how alcohol, polysubstance use and other factors influence opioid concentrations in drug-related deaths in West Virginia (WV), United States.

METHODS

Multiple linear regression models were employed to identify relationships among alcohol, other factors, and the concentrations of four commonly identified opioids (fentanyl, hydrocodone, oxycodone, methadone), accounting for demographic, toxicological and comorbid characteristics in WV drug-related deaths from 2005 to 2018.

RESULTS

Alcohol concentrations of 0.08% or above were associated with significant reductions in blood concentrations of fentanyl (27.5%), hydrocodone (30.5%) and methadone (32.4%). Significantly lower predicted concentrations of all opioids studied were associated with multiple opioid vs. single opioid presence, with predicted concentration reductions ranging from 13.7% for fentanyl to 65-66% for hydrocodone and oxycodone. Benzodiazepine presence was associated with small, non-statistically significant changes in opioid concentrations, while stimulant presence was associated with statistically significant reductions in hydrocodone and oxycodone concentrations.

CONCLUSIONS

Co-ingestion of alcohol, multiple opioids or stimulants were associated with significantly decreased predicted concentrations of commonly identified opioids in drug deaths. Further evidence is provided for enhanced risks from polysubstance use with opioids, which has important public health implications.

Discrepancies in Written Versus Calculated Durations in Opioid Prescriptions: Pre-Post Study

BACKGROUND

The United States is in the midst of an opioid epidemic. Long-term use of opioid medications is associated with an increased risk of dependence. The US Centers for Disease Control and Prevention makes specific recommendations regarding opioid prescribing, including that prescription quantities should not exceed the intended duration of treatment.

OBJECTIVE

The purpose of this study was to determine if opioid prescription quantities written at our institution exceed intended duration of treatment and whether enhancements to our electronic health record system improved any discrepancies.

METHODS

We examined the opioid prescriptions written at our institution for a 22-month period. We examined the duration of treatment documented in the prescription itself and calculated a duration based on the quantity of tablets and doses per day. We determined whether requiring documentation of the prescription duration affected these outcomes.

RESULTS

We reviewed 72,314 opioid prescriptions, of which 16.96% had a calculated duration that was greater than what was documented in the prescription. Making the duration a required field significantly reduced this discrepancy (17.95% vs 16.21%, P<.001) but did not eliminate it.

CONCLUSIONS

Health information technology vendors should develop tools that, by default, accurately represent prescription durations and/or modify doses and quantities dispensed based on provider-entered durations. This would potentially reduce unintended prolonged opioid use and reduce the potential for long-term dependence.

Fatal α-PVP and amphetamine poisoning during a sauna and autoerotic practices

We describe the sudden death of a middle-aged man while having a sauna under the influence of α-pyrrolidinovalerophenone (α-PVP) (PM blood concentration: 0.8 mg/L), amphetamine (0.34 mg/L), and other drugs (buprenorphine, benzodiazepines), and engaging in solitary sexual activities. The drugs’ effects on the cardio-circulatory system and on body thermoregulation combined with the high temperatures are likely to have been central mechanisms leading to death. The high levels of adrenaline triggered by sexual arousal and the respiratory depression caused by buprenorphine, in association with benzodiazepines, may have also contributed to his death. This previously unreported type of accidental autoerotic death illustrates the risk of using amphetamine-like sympathomimetic drugs (e.g. cathinone derivates) in hot environments such as a sauna, and during sexual activities therein.

Opioid-related deaths in Europe: Strategies for a comprehensive approach to address a major public health concern

Use of illicit opioids and misuse of prescription opioids are the main causes of drug-related deaths across the world, and the continuing rise in opioid-related mortality, especially affecting North America, Australia and Europe, is a public health challenge. Strategies that may help to decrease the high levels of opioid-related mortality and morbidity and improve care across Europe include risk assessment and interventions to improve the use of opioid analgesics, e.g. prescription drug-monitoring programmes, education on pain management to reduce opioid prescribing, and the implementation of evidence-based primary prevention programmes to reduce the demand for opioids. For patients who develop opioid use disorder (a chronic and relapsing problematic use of opioids that causes clinical impairment or distress), treatment combining opiate receptor full or partial agonist medications for opioid-use disorder (MOUD) with psychosocial interventions is essential. However, in Europe a substantial proportion of the 1.3 million high-risk opioid users (defined as injecting drug use or regular use of opioids, mainly heroin) remain outside of dedicated treatment programmes. More widespread and easier access to MOUD could reduce mortality levels; via approaches such as primary care-led treatment models, and efforts to improve patient retention and adherence to treatment programmes. Other harm-reduction strategies, such as the use of MOUD at optimal doses, the provision of take-home naloxone, the introduction of supervised drug-consumption facilities, and patient education to reduce the risk of overdose may also be beneficial.

Opioid-related deaths and previous care for drug use and pain relief in Sweden

AIM

In 2006-2014, the rate of drug-related deaths, typically opioid poisonings, more than doubled in Sweden. Opioid prescriptions for pain control or opioid agonist therapy also increased. In this retrospective study, we compared death rates between individuals whose first recorded contact with prescribed opioids was for pain control and individuals that had received substance use disorder (SUD) treatment before their first recorded opioid prescription.

METHODS

We included 2834 forensically examined individuals (ages 15-64 years) that died of poisoning in Sweden in 2006-2014. For each death we acquired data on previous opioid prescriptions and SUD treatments. We compared three study groups: pain control (n = 788); a SUD treatment group (n = 1629); and a group with no prescription for pain control or SUD treatment (n = 417).

RESULTS

Overall fatal poisonings increased from 2.77 to 7.79 (per 100,000 individuals) from 2006 to 2014 (relative 181% increase). Fatal poisoning increased from 2006 to 2014 by 269% in the pain control group (0.64 to 2.36 per 100,000) and by 238% in the SUD treatment group (1.35 to 4.57 per 100,000). Heroin-related deaths remained constant; consequently, the increase was likely attributable to prescription opioids.

CONCLUSION

A rapid increase in deaths attributable mainly to prescription opioids for pain control, was reported previously in the United States. Our study indicated that increased access to prescription opioids might contribute to higher death rates also in Sweden among patients seeking pain control and individuals with an established SUD; however, deaths related to prescription opioids mainly occurred among those with SUDs.

Graphene oxide-Fe3O4 nanocomposite magnetic solid phase extraction followed by UHPLC-MS/MS for highly sensitive determination of eight psychoactive drugs in urine samples

Graphene oxide-Fe₃O₄ (GO-Fe₃O₄) nanocomposite was synthesized by a facile chemical co-precipitation method. The GO-Fe₃O₄ was used as magnetic sorbent to extract the eight psychoactive drugs from urine samples. The analytes are morphine (MOR), 6-monoacetylmorphine (6-MAM), amphetamine (AMP), methamphetamine (MAMP), codeine, cocaine, dolantin and benzoylecgonine (BZE), which were determined by ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). This method has high selectivity for the target analytes. The limit of detection (LOD) and limit of quantification (LOQ) were 0.02-0.2 μg L^-1 and 0.05-0.5 μg L^-1, respectively. The Mandel's fitting test revealed good linearity within all linear ranges. The linear ranges were calculated as 0.05-1000 μg L^-1 for AMP, MAMP, cocaine and dolantin; 0.1-1000 μg L^-1 for 6-MAM and codein; and 0.5-1000 μg L^-1 for MOR and BZE. The recoveries ranged in 80.4-105.5%. The intra-day and inter-day RSDs are in the range of 2.7-13.1% and 3.9-13.7%, respectively. Magnetic solid phase extraction (MSPE) with GO-Fe₃O₄ provides a convenient, rapid and green sample pretreatment method for extracting the target psychoactive drugs from urine. This methodology can be used for simultaneous or individual detection of eight major psychoactive drugs with high sensitivity. This method has high potential in clinical and forensic areas for psychoactive drugs analysis.

Buprenorphine in the United States: Motives for abuse, misuse, and diversion

Opioid use disorder (OUD) and its consequences are a major public health concern. The partial agonist buprenorphine is a safe and effective treatment for OUD, but concerns about abuse, misuse, and diversion of buprenorphine have been raised. This narrative review examined the rates and motives for use of illicit buprenorphine in the United States. Findings from the 17 included studies suggest the majority of study participants using illicit buprenorphine do so for reasons related to misuse (to manage opioid withdrawal symptoms or achieve or maintain abstinence from other opioids). A smaller percentage of study respondents reported using buprenorphine for reasons related to abuse (to get high). There appears to be a gap between need for buprenorphine and access to adequate treatment. Attenuation of policy-related barriers and adoption of appropriate buprenorphine use by the treatment community are critical tools in the continued effort to reduce the burdens associated with OUD.

Liver Procurement from Poisoned Donors: A Survival Study

OBJECTIVES

Although transplant teams understand the effects of donor characteristics on liver transplant outcomes, few studies have investigated the quality of livers obtained from poisoned donors. The aim of this study was to compare livers procured from poisoned donors with a matched control group.

MATERIALS AND METHODS

Liver transplant outcomes from poisoned donors and from donors with trauma-induced death (as the control group) were compared using data of an Organ Procurement Unit from 2000 to 2013. Procured livers were evaluated via histology findings before transplant. Recipient characteristics were assessed in both groups, and immediate and medium-term (up to 5 years after transplant) survival rates were compared with the use of Kaplan-Meier analyses and log-rank tests.

RESULTS

Over a 13-year organ donation program, 1485 livers from brain dead patients were donated. Among them, 115 poisoned donors were evaluated for liver grafts; of these, 74 successful liver transplants were performed. In the poisoned donors, the incidence of reversed cardiac arrest was 54.1%. Likewise, acute kidney injury was detected in 14.9% of the patients, and 16.2% needed urgent dialysis either for clearance of the toxic agents or for treatment of acute kidney injury. No significant differences were observed in 1- to 5-year survival rates, and log-rank test also showed a significance level of 0.83.

CONCLUSIONS

Proper case selection strategies can be implemented to expand the donor pool, including use of poisoned donors. Hence, poisoning is not a contra-indication for a referral, which could lead to decreased mortality for patients requiring a liver transplant.

Association of Tramadol With All-Cause Mortality Among Patients With Osteoarthritis

IMPORTANCE

An American Academy of Orthopaedic Surgeons guideline recommends tramadol for patients with knee osteoarthritis, and an American College of Rheumatology guideline conditionally recommends tramadol as first-line therapy for patients with knee osteoarthritis, along with nonsteroidal anti-inflammatory drugs.

OBJECTIVE

To examine the association of tramadol prescription with all-cause mortality among patients with osteoarthritis.

DESIGN, SETTING, AND PARTICIPANTS

Sequential, propensity score-matched cohort study at a general practice in the United Kingdom. Individuals aged at least 50 years with a diagnosis of osteoarthritis in the Health Improvement Network database from January 2000 to December 2015, with follow-up to December 2016.

EXPOSURES

Initial prescription of tramadol (n = 44 451), naproxen (n = 12 397), diclofenac (n = 6512), celecoxib (n = 5674), etoricoxib (n = 2946), or codeine (n = 16 922).

MAIN OUTCOMES AND MEASURES

All-cause mortality within 1 year after initial tramadol prescription, compared with 5 other pain relief medications.

RESULTS

After propensity score matching, 88 902 patients were included (mean [SD] age, 70.1 [9.5] years; 61.2% were women). During the 1-year follow-up, 278 deaths (23.5/1000 person-years) occurred in the tramadol cohort and 164 (13.8/1000 person-years) occurred in the naproxen cohort (rate difference, 9.7 deaths/1000 person-years [95% CI, 6.3-13.2]; hazard ratio [HR], 1.71 [95% CI, 1.41-2.07]), and mortality was higher for tramadol compared with diclofenac (36.2/1000 vs 19.2/1000 person-years; HR, 1.88 [95% CI, 1.51-2.35]). Tramadol was also associated with a higher all-cause mortality rate compared with celecoxib (31.2/1000 vs 18.4/1000 person-years; HR, 1.70 [95% CI, 1.33-2.17]) and etoricoxib (25.7/1000 vs 12.8/1000 person-years; HR, 2.04 [95% CI, 1.37-3.03]). No statistically significant difference in all-cause mortality was observed between tramadol and codeine (32.2/1000 vs 34.6/1000 person-years; HR, 0.94 [95% CI, 0.83-1.05]).

CONCLUSIONS AND RELEVANCE

Among patients aged 50 years and older with osteoarthritis, initial prescription of tramadol was associated with a significantly higher rate of mortality over 1 year of follow-up compared with commonly prescribed nonsteroidal anti-inflammatory drugs, but not compared with codeine. However, these findings may be susceptible to confounding by indication, and further research is needed to determine if this association is causal.

From Substance Use Disorders in Life to Autopsy Findings: A Combined Case-Record and Medico-Legal Study

Objectives: Several studies have shown mortality and suicide risk in substance use disorders, and autopsy findings with respect to the used substances. However, there seems to be a gap in the knowledge about substances misused in life and at death at the within-person level. Methods: All consecutive, autopsied patients during 1993 to 1997, who had been in contact with the Addiction Centre in Malmö from 1968, were investigated (365 subjects). Drug misuse in the long-term course noted in case records was related to autopsy findings. Self-inflicted death (suicide/undetermined suicide/accidental overdose) was compared with natural death. Results: Benzodiazepine misuse was associated with a high risk of autopsy findings of the substance in suicide and death of undetermined intent. It was also associated among non-misusers, but less so. An alcohol level above 1‰ was found more often in self-inflicted death. Prescription opioids at autopsy were mainly found in self-inflicted death among non-misusers. Heroin misuse was related to overdose. Central nervous system stimulants (CNS-S) and cannabis were rarely found in self-inflicted death among previous misusers. The overlap between depression in life and antidepressants at death was low. Conclusions: Benzodiazepines and alcohol seem to disinhibit suicidal tendencies. Suicide risk among users of cannabis and CNS-S may be related to other risk factors than acute use. Implications for suicide prevention are discussed.

Relative toxicity of analgesics commonly used for intentional self-poisoning: A study of case fatality based on fatal and non-fatal overdoses

BACKGROUND

Analgesics are used most frequently in fatal and non-fatal medicinal self-poisonings. Knowledge about their relative toxicity in overdose is important for clinicians and regulatory agencies.

METHODS

Using data for 2005-2012 we investigated case fatality (number of suicides relative to number of non-fatal self-poisonings) of paracetamol, aspirin, codeine, dihydrocodeine, tramadol, paracetamol with codeine (co-codamol), paracetamol with dihydrocodeine (co-dydramol), ibuprofen and co-proxamol (paracetamol plus dextropropoxyphene; withdrawn in the UK in 2008 due to high toxicity). Data on suicides obtained from the Office for National Statistics and on non-fatal self-poisonings from the Multicentre Study of Self-harm in England. Case fatality was estimated for each drug, using paracetamol as the reference category.

RESULTS

Compared to paracetamol and based on single drug deaths the case fatality index of dihydrocodeine was considerably elevated (odds ratio (OR) 12.81, 95% Confidence Interval (CI) 10.19-16.12). Case fatality indices for tramadol (OR 4.05, 95% CI 3.38-4.85) and codeine (OR 2.21, 95% CI 1.81-2.70) were also significantly higher than for paracetamol. The results when multiple drug deaths were included produced similar results. The relative toxicity of co-proxamol far exceeded that of the other analgesics.

LIMITATIONS

Data on fatal self-poisonings were based on national data, whereas those for non-fatal poisonings were based on local data.

CONCLUSIONS

Dihydrocodeine and tramadol are particularly toxic in overdose and codeine is also relatively toxic. They should be prescribed with caution, particularly to individuals at risk of self-harm.

Novel Synthetic Opioids: The Pathologist's Point of View

Background: New Psychoactive Substances (NPS) constitute a broad range of hundreds of natural and synthetic drugs, including synthetic opioids, synthetic cannabinoids, synthetic cathinones, and other NPS classes, which were not controlled from 1961 to 1971 by the United Nations drug control conventions. Among these, synthetic opioids represent a major threat to public health. Methods: A literature search was carried out using public databases (such as PubMed, Google Scholar, and Scopus) to survey fentanyl-, fentanyl analogs-, and other synthetic opioid-related deaths. Keywords including “fentanyl”, “fentanyl analogs”, “death”, “overdose”, “intoxication”, “synthetic opioids”, “Novel Psychoactive Substances”, “MT-45”, “AH-7921”, and “U-47700” were used for the inquiry. Results: From our literature examination, we inferred the frequent implication of fentanyls and synthetic opioids in side effects, which primarily affected the central nervous system and the cardiovascular and pulmonary systems. The data showed a great variety of substances and lethal concentrations. Multidrug-related deaths appeared very common, in most reported cases. Conclusions: The investigation of the contribution of novel synthetic opioid intoxication to death should be based on a multidisciplinary approach aimed at framing each case and directing the investigation towards targeted toxicological analyses.

Recent trends in life expectancy across high income countries: retrospective observational study

OBJECTIVES

To assess whether declines in life expectancy occurred across high income countries during 2014-16, to identify the causes of death contributing to these declines, and to examine the extent to which these declines were driven by shared or differing factors across countries.

DESIGN

Demographic analysis using aggregated data.

SETTING

Vital statistics systems of 18 member countries of the Organisation for Economic Co-operation and Development.

PARTICIPANTS

18 countries with high quality all cause and cause specific mortality data available in 2014-16.

MAIN OUTCOME MEASURES

Life expectancy at birth, 0-65 years, and 65 or more years and cause of death contributions to changes in life expectancy at birth.

RESULTS

The majority of high income countries in the study experienced declines in life expectancy during 2014-15; of the 18 countries, 12 experienced declines in life expectancy among women and 11 experienced declines in life expectancy among men. The average decline was 0.21 years for women and 0.18 years for men. In most countries experiencing declines in life expectancy, these declines were predominantly driven by trends in older age (≥65 years) mortality and in deaths related to respiratory disease, cardiovascular disease, nervous system disease, and mental disorders. In the United States, declines in life expectancy were more concentrated at younger ages (0-65 years), and drug overdose and other external causes of death played important roles in driving these declines.

CONCLUSIONS

Most of the countries that experienced declines in life expectancy during 2014-15 experienced robust gains in life expectancy during 2015-16 that more than compensated for the declines. However, the United Kingdom and the United States appear to be experiencing stagnating or continued declines in life expectancy, raising questions about future trends in these countries.

Oxycodone-induced tolerance to respiratory depression: reversal by ethanol, pregabalin and protein kinase C inhibition

BACKGROUND AND PURPOSE

Oxycodone, a prescription opioid, is a major drug of abuse, especially in the USA, and contributes significantly to opioid overdose deaths each year. Overdose deaths result primarily from respiratory depression. We have studied respiratory depression by oxycodone and have characterized how tolerance develops on prolonged exposure to the drug. We have investigated the role of PKC in maintaining tolerance and have examined whether ethanol or pregabalin reverses oxycodone-induced tolerance.

EXPERIMENTAL APPROACH

Respiration was measured in male CD-1 mice by whole-body plethysmography. Mice were preinjected with oxycodone then implanted with mini-pumps (s.c.) delivering 20, 45 or 120 mg·kg-1 ·day-1 oxycodone for 6 days and subsequently challenged with oxycodone (3 mg·kg-1 , i.p.) or morphine (10 mg·kg-1 , i.p.) to assess the level of tolerance.

KEY RESULTS

Oxycodone-treated mice developed tolerance to oxycodone and cross tolerance to morphine-induced respiratory depression. Tolerance was less with 20 mg·kg-1 ·day-1 than with 45 or 120 mg·kg-1 ·day-1 oxycodone treatment. At doses that do not depress respiration, ethanol (0.3 g·kg-1 ), pregabalin (20 mg·kg-1 ) and calphostin C (45 μg·kg-1 ) all reversed oxycodone-induced tolerance resulting in significant respiratory depression. Reversal of tolerance was less in mice treated with oxycodone (120 mg·kg-1 ·day-1 ). In mice receiving ethanol and calphostin C or ethanol and pregabalin, there was no greater reversal of tolerance than seen with either drug alone.

CONCLUSION AND IMPLICATIONS

These data suggest that oxycodone-induced tolerance is mediated by PKC and that reversal of tolerance by ethanol or pregabalin may be a contributory factor in oxycodone overdose deaths.

Pain Therapy Guided by Purpose and Perspective in Light of the Opioid Epidemic

Prescription opioid misuse is an ongoing and escalating epidemic. Although these pharmacological agents are highly effective analgesics prescribed for different types of pain, opioids also induce euphoria, leading to increasing diversion and misuse. Opioid use and related mortalities have developed in spite of initial claims that OxyContin, one of the first opioids prescribed in the USA, was not addictive in the presence of pain. These claims allayed the fears of clinicians and contributed to an increase in the number of prescriptions, quantity of drugs manufactured, and the unforeseen diversion of these drugs for non-medical uses. Understanding the history of opioid drug development, the widespread marketing campaign for opioids, the immense financial incentive behind the treatment of pain, and vulnerable socioeconomic and physical demographics for opioid misuse give perspective on the current epidemic as an American-born problem that has expanded to global significance. In light of the current worldwide opioid epidemic, it is imperative that novel opioids are developed to treat pain without inducing the euphoria that fosters physical dependence and addiction. We describe insights from preclinical findings on the properties of opioid drugs that offer insights into improving abuse-deterrent formulations. One finding is that the ability of some agonists to activate one pathway over another, or agonist bias, can predict whether several novel opioid compounds bear promise in treating pain without causing reward among other off-target effects. In addition, we outline how the pharmacokinetic profile of each opioid contributes to their potential for misuse and discuss the emergence of mixed agonists as a promising pipeline of opioid-based analgesics. These insights from preclinical findings can be used to more effectively identify opioids that treat pain without causing physical dependence and subsequent opioid abuse.

Food pyramid for subjects with chronic pain: foods and dietary constituents as anti-inflammatory and antioxidant agents

Emerging literature suggests that diet constituents may play a modulatory role in chronic pain (CP) through management of inflammation/oxidative stress, resulting in attenuation of pain. We performed a narrative review to evaluate the existing evidence regarding the optimum diet for the management of CP, and we built a food pyramid on this topic. The present review also describes the activities of various natural compounds contained in foods (i.e. phenolic compounds in extra-virgin olive oil (EVO)) listed on our pyramid, which have comparable effects to drug management therapy. This review included 172 eligible studies. The pyramid shows that carbohydrates with low glycaemic index should be consumed every day (three portions), together with fruits and vegetables (five portions), yogurt (125 ml), red wine (125 ml) and EVO; weekly: legumes and fish (four portions); white meat, eggs and fresh cheese (two portions); red or processed meats (once per week); sweets can be consumed occasionally. The food amounts are estimates based on nutritional and practical considerations. At the top of the pyramid there is a pennant: it means that CP subjects may need a specific customised supplementation (vitamin B12, vitamin D, n-3 fatty acids, fibre). The food pyramid proposal will serve to guide dietary intake with to the intent of alleviating pain in CP patients. Moreover, a targeted diet can also help to solve problems related to the drugs used to combat CP, i.e. constipation. However, this paper would be an early hypothetical proposal due to the limitations of the studies.

A 15-year overview of increasing tramadol utilisation and associated mortality and the impact of tramadol classification in the United Kingdom

PURPOSE

This study aimed to develop hypotheses to explain the increasing tramadol utilisation, evaluate the impact of tramadol classification, and explore the trend between tramadol utilisation and related deaths in the United Kingdom.

METHODS

This cross-sectional study used individual patient data, the Clinical Practice Research Datalink from 1993 to 2015, to calculate monthly defined daily dose (DDD)/1000 registrants, monthly prevalence and incidence of tramadol users, annual supply days, and mean daily dose of tramadol. Aggregated-level national statistics and reimbursement data from 2004 to 2015 were also used to quantify annual and monthly tramadol DDD/1000 inhabitants and rate of tramadol-related deaths in England and Wales. Interrupted time-series analysis was used to evaluate the impact of tramadol classification in June 2014.

RESULTS

Prevalence of tramadol users increased from 23 to 97.6/10 000 registrants from 2000 to 2015. Both annual dose and annual supply days of existing tramadol users were higher than new users. Level and trend of monthly utilisation (β₂ : -12.9, β₃ : -1.6) and prevalence of tramadol users (β₂ : -6.4, β₃ : -0.37) significantly reduced after classification. Both annual tramadol utilisation and rate of tramadol-related deaths increased before tramadol classification and decreased thereafter.

CONCLUSIONS

Increasing tramadol utilisation was influenced by the increase in prevalence and incidence of tramadol users, mean daily dose, and day of supply. Prevalence of tramadol users, tramadol utilisation, and reported deaths declined after tramadol classification. Future studies need to evaluate the influencing factors to ensure the safety of long-term tramadol use.

Do pre-hospital poisoning deaths differ from in-hospital deaths? A retrospective analysis

Background

Most fatal poisonings occur outside the hospital and the victims found dead. The purpose of this study was to determine the general pattern and patient demographics of fatal poisonings in Northern Finland. In particular, we wanted to analyze differences between pre-hospital and in-hospital deaths.

Methods

All fatal poisonings that occurred in Northern Finland in 2007–2011 were retrieved from the Cause of Death Registry provided by Statistics Finland. We noted the patient demographics, causal agents, and other characteristics of the poisoning events.

Results

A total of 689 fatal poisonings occurred during the study period, of which only 42 (6.1%) reached the hospital alive. Those who died pre-hospital were significantly younger (50 vs. 56 years, p = 0.04) and more likely to be male (77% vs. 57%, p = 0.003). Cardiopulmonary resuscitation was attempted less often in pre-hospital cases (9.9% vs. 47.6%, p < 0.001). Ethanol was more frequently the main toxic agent in pre-hospital deaths (58.4% vs. 26.2%, p < 0.001), and multiple ingestions were more common (52.2% vs. 35.7%, p < 0.001) in pre-hospital deaths.

Discussion

Most of the pre-hospital fatal poisoning victims are found dead and the majority of in-hospital victims are admitted to hospital in an already serious condition. According to results of this and former studies, prevention seems to be the most important factor in reducing deaths due to poisoning.

Conclusions

The majority of poisoning-related deaths occur pre-hospital and are related to alcohol intoxication and multiple ingestions.

Assessing the accuracy of opioid overdose and poisoning codes in diagnostic information from electronic health records, claims data, and death records

PURPOSE

The purpose of this study is to assess positive predictive value (PPV), relative to medical chart review, of International Classification of Diseases (ICD)-9/10 diagnostic codes for identifying opioid overdoses and poisonings.

METHODS

Data were obtained from Kaiser Permanente Northwest and Northern California. Diagnostic data from electronic health records, submitted claims, and state death records from Oregon, Washington, and California were linked. Individual opioid-related poisoning codes (e.g., 965.xx and X42), and adverse effects of opioids codes (e.g., E935.xx) combined with diagnoses possibly indicative of overdoses (e.g., respiratory depression), were evaluated by comparison with chart audits.

RESULTS

Opioid adverse effects codes had low PPV to detect overdoses (13.4%) as assessed in 127 charts and were not pursued. Instead, opioid poisoning codes were assessed in 2100 individuals who had those codes present in electronic health records in the period between the years 2008 and 2012. Of these, 10/2100 had no available information and 241/2100 were excluded potentially as anesthesia-related. Among the 1849 remaining individuals with opioid poisoning codes, 1495 events were accurately identified as opioid overdoses; 69 were miscodes or misidentified, and 285 were opioid adverse effects, not overdoses. Thus, PPV was 81%. Opioid adverse effects or overdoses were accurately identified in 1780 of 1849 events (96.3%).

CONCLUSIONS

Opioid poisoning codes have a predictive value of 81% to identify opioid overdoses, suggesting ICD opioid poisoning codes can be used to monitor overdose rates and evaluate interventions to reduce overdose. Further research to assess sensitivity, specificity, and negative predictive value are ongoing. Copyright © 2017 John Wiley & Sons, Ltd.

Fatal Overdoses of Opioids in Israel 2005-2014

AIMS

To explore previously unreported rates and trends in opioid-related mortality in Israel, 2005-2014.

METHODS

Data was obtained from the national database on causes of death. Drug poisoning deaths were divided into opioid-related deaths and deaths related to other drugs according to International Classification of Diseases (ICD)-10 code of underlying cause, and included drug poisoning of accidental, intentional or undetermined intent. Age-adjusted rates were calculated per 100,000 population. Rate ratios were calculated and a logistic model constructed to compare the risk of opioid-related deaths in both halves of the decade (2006-2009 and 2009-2013) and between various demographic groups.

RESULTS

While age-adjusted rates of deaths related to other drugs remained relatively stable, rates of opioid-related deaths significantly decreased during this period across all groups. During the study period, the number of opioid-related deaths in Israel declined from 1.3 to 0.3 per 100,000. Opioid-related deaths were more common among men, young adults and immigrants from the Former Soviet Union.

CONCLUSIONS

Rates of opioid-related deaths in Israel were low compared to those reported in the United States and United Kingdom. In addition, the decline in opioid-related deaths in Israel is contrary to trends observed in the United States and United Kingdom. Factors that may contribute to these differences are discussed.

Quantitative detection of codeine in human plasma using surface-enhanced Raman scattering via adaptation of the isotopic labelling principle

In this study surface-enhanced Raman scattering (SERS) combined with the isotopic labelling (IL) principle has been used for the quantification of codeine spiked into both water and human plasma.

Alcohol use in opioid agonist treatment

Alcohol misuse among individuals receiving agonist treatment for an opioid use disorder is common and is associated with significant morbidity and mortality. At present, though substantial research highlights effective strategies for the screening, diagnosis and management of an alcohol or opioid use disorder individually, less is known about how best to care for those with a dual diagnosis especially since common treatments for opioid addiction may be contraindicated in a setting of alcohol use. This review summarizes existing research and characterizes the prevalence, clinical implications and management of alcohol misuse among individuals with opioid addiction. Furthermore, it highlights clinically relevant management strategies in need of future research to advance care for this unique, but important, patient population.

Additive Effects of Cointoxicants in Single-Opioid Induced Deaths

A forensic drug database (FDD) was used to capture comprehensive data from all drug-related deaths in West Virginia, with deaths also included from the northern New England states of Maine, Vermont, and New Hampshire. All four states serve predominantly rural populations under two million and all have similar state medical examiner systems that employ statewide uniform death certification policies and practices. This study focused on 1482 single opioid deaths (fentanyl, hydrocodone, methadone, and oxycodone) in the FDD from 2007-2011. We modeled relationships between the opioid concentrations and the presence or absence of the following commonly occurring non-opioid cointoxicants: benzodiazepines (alprazolam and diazepam), alcohol, tricyclic antidepressants, selective serotonin reuptake inhibitors, and diphenhydramine. Additional covariates of state, age, body mass index, and sex were included. Results showed that the presence of alcohol, benzodiazepines, and antidepressants were each associated with statistically significant lower concentrations of some but not all of the opioids studied, which may obscure the interpretation of postmortem toxicology results alone. Fentanyl concentrations appeared to be the least associated with the presence or absence of the variables studied, and cointoxicant alcohol appeared to be associated with lower concentrations in opioid concentrations than were most of the other factors in the model studied. These findings underscore the importance of documenting all potential cointoxicants in opioid-related deaths.