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Tramadol is an opioid used in the treatment of moderate to moderately severe pain. Tramadol’s use during pregnancy is generally avoided and may cause some reversible withdrawal effects in neonates, and its use during lactation is not licensed by the manufacturer. A small clinical trial reported infants were exposed to

The use of electronic cigarettes (e-cigs) has expanded from a nicotine delivery system to a general drug delivery system. The internet is rife with websites, blogs and forums informing users how to modify e-cigs to deliver illicit drugs while maintaining optimal drug delivery of their device. The goal of this study was to qualitatively identify the presence of methamphetamine in the aerosol produced by an e-cig and to quantitatively assess the effect voltage on the concentration of aerosolized methamphetamine. A KangerTech AeroTank electronic cigarette containing a 30, 60 or 120 mg/mL of methamphetamine in 50:50 propylene glycol: vegetable glycerin formulation was used to produce the aerosol. To qualitatively identify aerosolized methamphetamine, the aerosol was generated at 4.3 V, trapped in a simple glass trapping system, extracted using solid-phase microextraction (SPME), and analyzed by high-resolution Direct Analysis in Real Time AccuTOF™ Mass Spectrometry (DART-MS). To assess the effect of voltage on the concentration of aerosolized methamphetamine, the aerosol was generated at 3.9, 4.3 and 4.7 V, trapped and quantified using gas chromatography mass spectrometry (GC/MS). SPME-DART-MS and SPME-GC-MS demonstrated the aerosolization of methamphetamine. The concentration of aerosolized methamphetamine at 3.9, 4.3 and 4.7 V was not statistically different at 800 ± 600 ng/mL, 800 ± 600 ng/mL and 1,000 ± 800 ng/mL, respectively. The characterization of the vapors produced from e-liquids containing methamphetamine provides an understanding of the dose delivery dynamics of e-cigarettes.

Opioid usage in the USA has increased over the past decade, with prescriptions increasing from 76 million in 1991 to 207 million in 2013. New regulations have curbed the number of prescriptions, leading to an increase in heroin use. Heroin-related overdoses have quadrupled between 2000 and 2015. The traditional urinary biomarkers for indicating heroin use are a combination of morphine and 6-acetyl morphine (6-AM). Morphine is detectable in urine for several days. 6-AM is detected in urine for 2–8 hours. Papaverine has been proposed as an alternative heroin biomarker. It has been reported to have a 1–2 day detection window. Papaverine metabolites have been reported to have up to a 3-day detection window. Presented is a method for the detection of papaverine and its metabolites, 6-desmethyl papaverine (6-DMP) and 4′, 6-didesmethyl papaverine (4,6-DDMP), in urine using a modified Waters® MCX™ microelution method. An ultra-performance liquid chromatography and tandem mass spectrometry (UPLC–MS-MS), with a Waters’ BEH C18 column, and 20 mM ammonium formate water: 20 mM ammonium formate methanol mobile phase was employed. Calibration curves were linear from 0.1 to 50 ng/mL. No interferences were observed from the analysis of multicomponent therapeutic drug or drugs of abuse control materials; intra- and inter-run precision tests were acceptable. A total of 428 genuine urine specimens where heroin use was suspected were analyzed. These included 101 6-AM and 179 morphine only positive samples as well as 6 morphine-negative samples where papaverine and/or metabolites were detected. The determined concentrations in these samples for papaverine, 6-DMP and 4,6-DDMP ranged from 0.10 to 994, 0.10 to 462 and 0.12 to 218 ng/mL, respectively. The method was rugged and robust for the analysis of papaverine and metabolites, 6-DMP and 4,6-DDMP. The use papaverine and metabolites, 6-DMP and 4,6-DDMP has the potential to increase the detection window of heroin use.

Presented is an ultra-high-pressure liquid chromatographic tandem mass spectrometry (UPLC–MS/MS) method developed for the detection of propylene glycol, glycerol, ethylene glycol and diethylene glycol using isotopically labeled standards in urine as part of ongoing studies to evaluate whether urinary propylene glycol and/or vegetable glycerin concentration are indicators of recent use. Propylene glycol and vegetable glycerol are found in many products that are consumed and used including electronic cigarettes (e-cigarettes). E-cigarettes are battery-powered devices used as an alternative to traditional cigarettes. The liquid formulations aerosolized in these devices largely consist of propylene glycol and/or vegetable glycerol. Published reports regarding the ratio of propylene glycol to glycerol content in these formulations ranged from 50:50 to 100 percent of either. For the analysis of urine specimens from both users and non-users of e-cigarettes, calibrators, controls and specimens were derivatized using benzoyl chloride prior to analysis. They were analyzed using a Waters AcQuity Xevo TQ-S Micro UPLC–MS/MS. Chromatographic separation was performed on an AcQuity UPLC BEH C18 1.7 um, 2.1 × 50 mm, column using a 20 mM ammonium formate in water and 20 mM ammonium formate in methanol as the mobile phase. The method was validated using SWGTOX guidelines for linearity, precision and accuracy, stability, carryover and limit of detection. The linear range was determined using a seven-point calibration curve ranging between 0.5 and 100 mcg/mL. The bias for all validation controls was determined to be ±20% of the expected concentrations with CVs of

Background: Paclitaxel-induced peripheral neuropathy (PIPN) is a major adverse effect of this chemotherapeutic agent that is used in the treatment of a number of solid malignancies. PIPN leads notably to burning pain, cold and mechanical allodynia. PIPN is thought to be a consequence of alterations of mitochondrial function, hyperexcitability of neurons, nerve fiber loss, oxidative stress and neuroinflammation in dorsal root ganglia (DRG) and spinal cord (SC). Therefore, reducing neuroinflammation could potentially attenuate neuropathy symptoms. Peroxisome proliferator-activated receptor-&alpha, (PPAR-&alpha, ) nuclear receptors that modulate inflammatory responses can be targeted by non-selective agonists, such as fenofibrate, which is used in the treatment of dyslipidemia. Methods: Our studies tested the efficacy of a fenofibrate diet (0.2% and 0.4%) in preventing the development of PIPN. Paclitaxel (8 mg/kg) was administered via 4 intraperitoneal (i.p.) injections in C57BL/6J mice (both male and female). Mechanical and cold hypersensitivity, wheel running activity, sensory nerve action potential (SNAP), sciatic nerve histology, intra-epidermal fibers, as well as the expression of PPAR-&alpha, and neuroinflammation were evaluated in DRG and SC. Results: Fenofibrate in the diet partially prevented the development of mechanical hypersensitivity but completely prevented cold hypersensitivity and the decrease in wheel running activity induced by paclitaxel. The reduction in SNAP amplitude induced by paclitaxel was also prevented by fenofibrate. Our results indicate that suppression of paclitaxel-induced pain by fenofibrate involves the regulation of PPAR-&alpha, expression through reduction in neuroinflammation. Finally, co-administration of paclitaxel and the active metabolite of fenofibrate (fenofibric acid) did not interfere with the suppression of tumor cell growth or clonogenicity by paclitaxel in ovarian and breast cancer cell lines. Conclusions: Taken together, our results show the therapeutic potential of fenofibrate in the prevention of PIPN development.

Electronic cigarettes (e-cigarettes) are an alternate nicotine delivery system that generate a condensation aerosol to be inhaled by the user. The size of the droplets formed in the aerosol can vary and contributes to drug deposition and ultimate bioavailability in the lung. The growing popularity of e-cigarette products has caused an increase in internet sources promoting the use of drugs other than nicotine (DOTNs) in e-cigarettes. The purpose of this study was to determine the effect of various e-cigarette and e-liquid modifications, such as coil resistance, battery voltage, and glycol and drug formulation, on the aerosol particle size. E-liquids containing 12 mg/mL nicotine prepared in glycol compositions of 100% propylene glycol (PG), 100% vegetable glycerin (VG), or 50:50 PG:VG were aerosolized at three voltages and three coil resistances. Methamphetamine and methadone e-liquids were prepared at 60 mg/mL in 50:50 PG:VG and all e-liquids were aerosolized onto a 10 stage Micro-Orifice Uniform Deposit Impactor. Glycol deposition correlated with drug deposition, and the majority of particles centered between 0.172–0.5 μm in diameter, representing pulmonary deposition. The 100% PG e-liquid produced the largest aerosol particles and the 100% VG and 50:50 PG:VG e-liquids produced ultra-fine particles

Background We describe a case of symptomatic bradycardia resulting from ivabradine toxicity by measurement of ivabradine levels, of which there are limited reports in the literature. Case presentation A 43-year-old White female presented with several days of near syncope and dizziness accompanied by a drop in her heart rate to 50 beats per minute. She was taking ivabradine for inappropriate sinus tachycardia. After excluding several other causes of bradycardia, we made the diagnosis of ivabradine toxicity by measurement of serum ivabradine levels, an approach that is currently not clinically available. Conclusions Measurement of serum ivabradine levels and knowledge of the pharmacokinetic properties of the drug can be utilized to confirm the diagnosis of ivabradine toxicity.

Background Antagonism of peripheral opioid receptors by methylnaltrexone (MNTX) was recently proposed as a potential mechanism to attenuate the development of opioid analgesic tolerance based on experiments conducted in mice. However, reports indicate that MNTX is demethylated to naltrexone (NTX) in mice, and NTX may subsequently cross the blood-brain barrier to antagonize centrally-mediated opioid effects. The goal of this study was to determine whether MNTX alters centrally-mediated behaviors elicited by the opioid analgesics, morphine and oxycodone, and to quantify concentrations of MNTX and NTX in blood and brain following their administration in mice. Methods Combinations of MNTX and morphine were tested under acute and chronic conditions in thermal nociceptive assays. Effects of MNTX and NTX pretreatment were assessed in an oxycodone discrimination operant procedure. Blood and brain concentrations of these antagonists were quantified after their administration using liquid chromatography-mass spectrometry. Results MNTX dose-dependently attenuated acute and chronic morphine antinociception. MNTX and NTX dose-dependently antagonized the discriminative stimulus effects of oxycodone. MNTX and NTX were detected in both blood and brain after administration of MNTX, confirming its demethylation and demonstrating that MNTX itself can cross the blood-brain barrier. Conclusions These results provide converging behavioral and analytical evidence that MNTX administration in mice attenuates centrally-mediated effects produced by opioid analgesics and results in functional concentrations of MNTX and NTX in blood and brain. Collectively, these findings indicate that MNTX cannot be administered systemically in mice for making inferences that its effects are peripherally restricted.

Rationale Natural plant products have been used to promote health, prevent sickness, and treat various ailments. These products often consist of leaves, flowers, bark, roots, seeds, and/or other parts of the plant. Many of the pharmacologically active constituents of these products are known, but the pharmacology of these constituents may not be fully elucidated. Natural plant-based products are also available in various forms other than the raw plant material. A wide array of commercial products such as capsules, powders, extracts, and electronic cigarette (e-cigarette) electronic liquids (e-liquids) are readily available and can be purchased from various outlets, both store-based retailers and online. Newer e-cigarettes are often advertised as "heat not burn" and are used for "vaping" various forms of extracts including "waxes" and "dabs" and raw plant material. Methods A single manufacturer was found online selling "24 different herbs" in powders, extracts, or e-liquids. These were advertised as "legal in the USA" and each product listed multiple effects. Eight e-liquids, six extracts (resins), and four powders from eight different "herbs," namely African dream, areca nut, blue lotus, damiana, kra thum na, kra thum kok, klip dagga, and wild lettuce, were purchased. An advertisement for these products stated, "Most people use the leaves, powder or resin in vaporizers." Direct analysis in real time AccuTOF™ mass spectrometry (DART-MS) was used to identify the psychoactive components in the natural products. Results The psychoactive compounds that were identified in only two of the eight e-liquids, three of the five resins, and three of the four powders were arecaidine, arecoline, coumarin, entadamide, mitragynine, 7-hydroxymitragynine, and nuciferine. Conclusions Psychoactive and potentially harmful substances were present in the powders and resins of the natural products. The newer types of e-cigarettes made for consuming natural products may increase their abuse potential.

The HIV-1 transactivator of transcription (Tat) is a neurotoxin involved in the pathogenesis of HIV-1 associated neurocognitive disorders (HAND). The neurotoxic effects of Tat are mediated directly via AMPA/NMDA receptor activity and indirectly through neuroinflammatory signaling in glia. Emerging strategies in the development of neuroprotective agents involve the modulation of the endocannabinoid system. A major endocannabinoid, anandamide (N-arachidonoylethanolamine, AEA), is metabolized by fatty acid amide hydrolase (FAAH). Here we demonstrate using a murine prefrontal cortex primary culture model that the inhibition of FAAH, using PF3845, attenuates Tatmediated increases in intracellular calcium, neuronal death, and dendritic degeneration via cannabinoid receptors (CB(1)R and CB(2)R). Live cell imaging was used to assess Tat-mediated increases in [Ca(2+)](i), which was significantly reduced by PF3845. A time-lapse assay revealed that Tat potentiates cell death while PF3845 blocks this effect. Additionally PF3845 blocked the Tatmediated increase in activated caspase-3 (apoptotic marker) positive neurons. Dendritic degeneration was characterized by analyzing stained dendritic processes using Imaris and Tat was found to significantly decrease the size of processes while PF3845 inhibited this effect. Incubation with CB(1)R and CB(2)R antagonists (SR141716A and AM630) revealed that PF3845-mediated calcium effects were dependent on CB(1)R, while reduced neuronal death and degeneration was CB(2)R-mediated. PF3845 application led to increased levels of AEA, suggesting the observed effects are likely a result of increased endocannabinoid signaling at CB(1)R/CB(2)R. Our findings suggest that modulation of the endogenous cannabinoid system through inhibition of FAAH may be beneficial in treatment of HAND.

Head-twitch behavior (HTR) is the behavioral signature of psychedelic drugs upon stimulation of the serotonin 5-HT2A receptor (5-HT2AR) in rodents. Following the previous report of a semi-automated detection of HTR based on the dynamics of mouse’s head movement, here we present a system for the identification of individual HTR events in a fully automated fashion. The validity of this fully automated HTR detection system was tested with the psychedelic drug DOI in 5-HT2AR-KO mice, and via evaluation of potential sources of false-positive and false-negative HTR events. The increased throughput in data processing achieved via automation afforded the possibility of conducting otherwise time consuming HTR time-course studies. To further assess the versatility of our system, we also explored the pharmacological interactions between 5-HT2AR and the metabotropic glutamate receptor 2 (mGluR2). Our data demonstrate the potentiation effect of the mGluR2/3 antagonist LY341495 on DOI-induced HTR, as well as the HTR-blocking effect of the mGluR2/3 agonist and antipsychotic drug in development LY404039. This fully automated system can contribute to speed up our understanding of 5-HT2AR’s pharmacology and its characteristic behavioral outputs in rodents.

BACKGROUND: Complex interactions between environmental and genetic factors influence the risk for developing alcohol use disorder (AUD) in humans. To date, studies of the impact of environment on AUD risk have primarily focused on psychological characteristics or on the effects of developmental exposure to ethanol. We recently observed that modifying levels of the long-chain ω-3 (LC ω-3) fatty acid, eicosapentaenoic acid (EPA), alters acute physiological responses to ethanol in C. elegans. Because mammals derive ω-3 fatty acids from their diet, here we asked if manipulating dietary levels of LC ω-3 fatty acids can affect ethanol-responsive behaviors in mice. METHODS: We used two well-characterized inbred mouse strains, C57BL/6J (B6) and DBA/2J (D2), that differ in their responses to ethanol. Age-matched young adult male mice were maintained on isocaloric diets that differed only by being enriched or depleted in LC ω-3 fatty acids. Animals were subsequently tested for acute ethanol sensitivity (locomotor activation and sedation), voluntary consumption, and metabolism. Fat deposition was also determined. RESULTS: We found that dietary levels of LC ω-3s altered ethanol sensitivity and consumption in a genotype-specific manner. Both B6 and D2 animals fed high LC ω-3 diets demonstrated lower ethanol-induced locomotor stimulation than those fed low LC ω-3 diets. Ethanol sedation and ethanol metabolism were greater in D2, but not B6 mice on the high LC ω-3 diet. Conversely, LC ω-3 dietary manipulation altered ethanol consumption in B6, but not in D2 mice. B6 mice on a high LC ω-3 diet consumed more ethanol in a 2-bottle choice intermittent access model than B6 mice on a low LC ω-3 diet. CONCLUSIONS: Because ethanol sensitivity is predictive of risk for developing AUD in humans, our data indicate that dietary LC ω-3 levels should be evaluated for their impact on AUD risk in humans. Further, these studies indicate that genetic background can interact with fatty acids in the diet to significantly alter ethanol-responsive behaviors.

Although paclitaxel effectively treats various cancers, its debilitating peripheral neuropathic pain side effects often persist long after treatment has ended. Therefore, a compelling need exists for the identification of novel pharmacologic strategies to mitigate this condition. As inhibitors of monoacylglycerol lipase (MAGL), the primary hydrolytic enzyme of the endogenous cannabinoid, 2-arachidonyolglycerol, produces antinociceptive effects in numerous rodent models of pain, we investigated whether inhibitors of this enzyme (i.e., JZL184 and MJN110) would reverse paclitaxel-induced mechanical allodynia in mice. These drugs dose dependently reversed allodynia with respective ED(50) values (95% confidence limit) of 8.4 (5.2–13.6) and 1.8 (1.0–3.3) mg/kg. Complementary genetic and pharmacologic approaches revealed that the antiallodynic effects of each drug require both cannabinoid receptors, CB(1) and CB(2). MJN110 reduced paclitaxel-mediated increased expression of monocyte chemoattractant protein-1 (MCP-1, CCL2) and phospho-p38 MAPK in dorsal root ganglia as well as MCP-1 in spinal dorsal horn. Whereas the antinociceptive effects of high dose JZL184 (40 mg/kg) underwent tolerance following 6 days of repeated dosing, repeated administration of a threshold dose (i.e., 4 mg/kg) completely reversed paclitaxel-induced allodynia. In addition, we found that the administration of MJN110 to control mice lacked intrinsic rewarding effects in the conditioned place preference (CPP) paradigm. However, it produced a CPP in paclitaxel-treated animals, suggesting a reduced paclitaxel-induced aversive state. Importantly, JZL184 did not alter the antiproliferative and apoptotic effects of paclitaxel in A549 and H460 non-small cell lung cancer cells. Taken together, these data indicate that MAGL inhibitors reverse paclitaxel-induced neuropathic pain without interfering with chemotherapeutic efficacy.

The NLRP3 inflammasome is an essential component of the innate immune system and has been implicated in neurodegenerative and inflammatory disorders. Therefore, there is increasing interest to develop inhibitors of the NLRP3 inflammasome to achieve disease intervention. Recently, we have developed a series of sulfonamide-based NLRP3 inhibitors as potential treatments for neurodegenerative diseases. One of the challenges for CNS therapeutics is blood-brain barrier penetration. Therefore, a method to detect and compare the blood-brain barrier penetration of these inhibitors is required but has not yet been established. In this study, we established a method to evaluate and quantify the blood-brain barrier penetration of JC-171, one of our lead NLRP3 inhibitors in comparison with MCC950, another known urea-based NLRP3 inhibitor using high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method. The results suggest that this methodology has the ability to provide reliable measurements for brain exposure.

The renal medulla, considered critical for the regulation of salt and water balance and long-term blood pressure control, is enriched in anandamide and two of its major metabolizing enzymes, cyclooxygenase-2 (COX-2) and fatty acid amide hydrolase (FAAH). Infusion of anandamide (15, 30, and 60 nmol·min−1·kg−1) into the renal medulla of C57BL/6J mice stimulated diuresis and salt excretion in a COX-2- but not COX-1-dependent manner. To determine whether endogenous endocannabinoids in the renal medulla can elicit similar effects, the effects of intramedullary isopropyl dodecyl fluorophosphate (IDFP), which inhibits the two major endocannabinoid hydrolases, were studied. IDFP treatment increased the urine formation rate and sodium excretion in a COX-2- but not COX-1-dependent manner. Neither anandamide nor IDFP affected the glomerular filtration rate. Neither systemic (0.625 mg·kg−1·30 min−1 iv) nor intramedullary (15 nmol·min−1·kg−1·30 min−1) IDFP pretreatment before intramedullary anandamide (15–30 nmol·min−1·kg−1) strictly blocked effects of anandamide, suggesting that hydrolysis of anandamide was not necessary for its diuretic effect. Intramedullary IDFP had no effect on renal blood flow but stimulated renal medullary blood flow. The effects of IDFP on urine flow rate and medullary blood flow were FAAH-dependent as demonstrated using FAAH knockout mice. Analysis of mouse urinary PGE2 concentrations by HPLC-electrospray ionization tandem mass spectrometry showed that IDFP treatment decreased urinary PGE2. These data are consistent with a role of FAAH and endogenous anandamide acting through a COX-2-dependent metabolite to regulate diuresis and salt excretion in the mouse kidney.

We present the case histories, autopsy findings and toxicology findings of two fatal intoxications involving the designer drug, butyryl fentanyl. The quantitative analysis of butyryl fentanyl in postmortem fluids and tissues was performed by an ultrahigh-performance liquid chromatography tandem mass spectrometry method. In the first case, butyryl fentanyl was the only drug detected with concentrations of 99 ng/mL in peripheral blood, 220 ng/mL in heart blood, 32 ng/mL in vitreous humor, 590 ng/mL in gastric contents, 93 ng/g in brain, 41 ng/g in liver, 260 ng/mL in bile and 64 ng/mL in urine. The cause of death was ruled fatal intoxication by butyryl fentanyl. In the second case, butyryl fentanyl was detected along with acetyl fentanyl, alprazolam and ethanol. The butyryl fentanyl concentrations were 3.7 ng/mL in peripheral blood, 9.2 ng/mL in heart blood, 9.8 ng/mL in vitreous humor, 4,000 ng/mL in gastric contents, 63 ng/g in brain, 39 ng/g in liver, 49 ng/mL in bile and 2 ng/mL in urine. The acetyl fentanyl concentrations were 21 ng/mL in peripheral blood, 95 ng/mL in heart blood, 68 ng/mL in vitreous humor, 28,000 ng/mL in gastric contents, 200 ng/g in brain, 160 ng/g in liver, 330 ng/mL in bile and 8 ng/mL in urine. In addition, the alprazolam concentration was 40 ng/mL and the ethanol concentration was 0.11 g/dL, both measured in peripheral blood. The cause of death in the second case was ruled a mixed drug intoxication. In both cases, the manner of death was accident.

Personal battery-powered vaporizers or electronic cigarettes were developed to deliver a nicotine vapor such that smokers could simulate smoking tobacco without the inherent pathology of inhaled tobacco smoke. With four states within the USA having legalized the cultivation, distribution and recreational use of marijuana and an additional 23 states plus the District of Columbia with laws that legalize marijuana in some form, it was inevitable that suppliers of legal marijuana would develop marijuana products for use in these electronic cigarettes. Presented is the analysis of one such marijuana electronic cigarette formulation sold under the brand name Liberty Reach. The cannabinoid concentrations in Liberty Reach as determined by high-performance liquid chromatography-triple quadrapole mass spectrometry (HPLC-MS-MS) were Δ9-tetrahydrocannabinol, 42.6% (w/v) and cannabidiol 0.5% (w/v). These concentrations were significantly lower than the labeled 69% Δ9-tetrahydrocannabinol and 1% cannabidiol. Furthermore, 4 cannabinoids, 13 marijuana terpenes, and propylene glycol were identified by a combination of Direct Analysis in Real Time-AccuTOF™ mass spectrometry (DART-MS), HPLC-MS-MS and gas chromatography-MS.

In the last two years, an epidemic of 40 fatal heroin overdose cases has occurred in the Tampa area of Florida. Of these cases, 14 involved fentanyl and acetyl fentanyl. Victim demographics, case histories, toxicology findings, and causes and manners of death for all 40 deaths are presented. In 26 deaths in which acetyl fentanyl or fentanyl were not involved, free and total peripheral blood morphine concentrations were consistent with fatal heroin intoxications, averaging 0.16 mg/L and 0.35 mg/L, respectively. In the heroin cases with fentanyl present (n=7), the average free morphine concentration was 0.040 mg/L, the average total morphine concentration was 0.080 mg/L, and the average fentanyl concentration was 0.012 mg/L. In the cases with heroin, fentanyl, and acetyl fentanyl (n=3), the average free morphine concentration was 0.010 mg/L, the average total morphine concentration was 0.030 mg/L, the average fentanyl concentration was 0.018 mg/L, and the average acetyl fentanyl concentration was 0.008 mg/L. In the cases involving only acetyl fentanyl (without heroin or fentanyl, n=4), the average acetyl fentanyl concentration was 0.47 mg/L and the average acetyl norfentanyl concentration was 0.053 mg/L. The presented cases, with associated drug concentrations, case histories, demographics, and causes and manners of death may help provide assistance with the interpretation of the postmortem findings. Based on case circumstances, autopsy results, and toxicology results, it is evident that fentanyl and/or acetyl fentanyl, when present, contributed to the cause of death.