Naloxone Research Articles

Med Check: Updates to Clozapine REMS, Weekly Treatment for OUD, and More

Back to table of contents Previous article Next article Med CheckFull AccessMed Check: Updates to Clozapine REMS, Weekly Treatment for OUD, and MoreTerri D’ArrigoTerri D’ArrigoSearch for more papers by this authorPublished Online:2 Sep 2021https://doi.org/10.1176/appi.pn.2021.9.1FDA Updates Clozapine REMSIn July the Food and Drug Administration (FDA) approved modifications to the Clozapine Risk Evaluation and Mitigation Strategy (REMS). Several of these changes affect health professionals who prescribe clozapine.Beginning on November 15, the Clozapine REMS requires a New Patient Status Form to document monitoring for all outpatients. This form must be submitted monthly.All health professionals who prescribe clozapine must be recertified by November 15 to continue prescribing the medication and they must re-enroll their patients who will continue taking the medication. Patients who are not re-enrolled by November 15 will no longer be able to receive clozapine.Information on recertifying and re-enrolling in the Clozapine REMS is posted hereWeekly OUD Treatment Gets Fast Track DesignationLyndra Therapeutics’ investigational weekly treatment for opioid use disorder (OUD), LYN-014, has received a fast track designation from the FDA, the company announced in July. LYN-014 is an oral, ultra-long-acting, extended-release levomethadone capsule. The FDA fast track is a process designed to facilitate the development of drugs that treat serious conditions and fill an unmet medical need and expedite their review.Levomethadone, is an enantiomer of racemic methadone (its molecules are a mirror image of those in racemic methadone). Levomethadone is not approved for use in the United States, although it has been approved for use in Europe since the 1960s for pain management and medication treatment for OUD.In April the FDA granted LYN-014 Investigational New Drug status, which enabled Lyndra to initiate a phase 1 clinical trial in patients whose OUD is currently controlled on daily oral immediate-release methadone.FDA Grants Breakthrough Therapy Designation to Investigational Narcolepsy TreatmentIn July Takeda Pharmaceutical Co. Ltd. announced that the FDA granted Breakthrough Therapy designation to TAK-994, the company’s investigational oral orexin agonist for the treatment of excessive daytime sleepiness in patients with narcolepsy type 1. The FDA’s Breakthrough Therapy designation expedites the development and review of drugs for serious conditions. The criteria for Breakthrough Therapy designation require preliminary clinical evidence that indicate that the drug may demonstrate substantial improvement over available therapy on at least one clinically significant endpoint.According to a statement by Takeda, the FDA’s decision to grant the Breakthrough Therapy designation was based in part on early phase and preliminary clinical data suggesting that the drug demonstrates substantially improved objective and subjective measurements of daytime wakefulness in patients with narcolepsy type 1.FDA to Review Diazepam Buccal FilmThe FDA will review Libervant (diazepam) buccal film for the treatment of acute uncontrolled seizures in patients with refractory epilepsy on stable regimens of antiepileptic drugs, Aquestive Therapeutics announced in July.A phase 1/2 open-label trial of 31 patients with seizure disorders who took antiepileptic drugs found that treatment with Libervant resulted in similar systemic exposures to Diastat diazepam rectal gel, the standard treatment.Aquestive originally submitted a New Drug Application (NDA) for Libervant in February 2020, but in September 2020 the FDA issued a Complete Response Letter stating that the study showed a lower drug exposure level than desired in certain weight groups. The letter also noted a number of protocol deviates in blood draws in one of the studies that was included in the NDA. In response, the company provided additional analysis as part of the NDA submission now under FDA review.Kloxxado Now Available to Treat Opioid OverdoseHikma Pharmaceuticals PLC’s nasal spray Kloxxado (naloxone hydrocloride) for the emergency treatment of opioid overdose is now available, the company announced in August. Kloxxado, which was approved by the FDA in April, delivers 8 mg of naloxone directly into the nasal cavity. The FDA had previously approved 2 mg and 4 mg naloxone nasal spray products.The FDA approved Kloxxado based on previous findings about the safety and effectiveness of Narcan injection (naloxone hydrochloride) for treating opioid overdose. Hikma Pharmaceuticals also submitted its own safety and effectiveness data. ■ ISSUES NewArchived

Self-Adaptive Particle Swarm Optimization of CT Images for Diagnosis of Severe Traumatic Brain Injury

This paper aimed to explore the application values of computed tomography (CT) imaging in the treatment of patients with severe traumatic brain injury (STBI), to provide help in the treatment of STBI. In this study, 86 patients with STBI were selected as the research objects and examined by CT based on a self-adaptive particle swarm algorithm (APSO). Besides, patients were treated with hyperbaric oxygen, high-dose hormone shock, and naloxone hydrochloride. The results showed that there was a locally low-density brain contusion and laceration injury area, spot-like high-density hemorrhage, and subarachnoid hemorrhage in the images of CT examination. The ventricles of diffuse brain injury were compressed and reduced, and the white matter indicated that the ventricles and cisterns became smaller. Asymmetric hemorrhage and subarachnoid hemorrhage were scattered at the white matter junction. In short, subarachnoid hemorrhage, spot-like high-density hemorrhage at the injury site, and diminished ventricles were typical CT imaging manifestations of STBI. Naloxone hydrochloride method could effectively alleviate the matrix metalloproteinase-9 (MMP-9) (23.47 ± 3.45) and S100 calcium-binding protein B (S100B) (0.16 ± 0.06) of patients, which had reliable guiding significance for the later CT examination clinically.

FDA approves higher dosage of naloxone nasal spray to treat opioid overdose

The U.S. Food and Drug Administration has approved a higher dose naloxone hydrochloride nasal spray product to treat opioid overdose.

Formulation of a recombinant HIV‐1 polytope candidate vaccine with naloxone/alum mixture: induction of multi‐cytokine responses with a higher regulatory mechanism

The potency of a vaccine highly depends upon the nature of the adjuvant used. There are a variety of ineffective vaccines, such as HIV-1 vaccine candidates, that need to be optimized with new adjuvant formulations to improve vaccine potency and efficacy. Studies show the potency of naloxone (NLX)/alum mixture in the induction of Th1/Th2 response for vaccine. However, other immunologic patterns inducing by this adjuvant and its immunoregulatory effect is unclear. In this regard, the aim of the present study was to investigate the effect of the NLX/alum mixture, as an adjuvant, on cytokine networks and immunoregulatory activity for an HIV-1 polytope vaccine. BALB/c mice were divided into six groups (n=6) and immunized subcutaneously with 10 μg of the vaccine formulated with NLX/alum, NLX, alum, and Freund's adjuvants. At the same time, the mice in the control groups received an equal volume of PBS or NLX. The lymphocyte proliferation assay was carried out using the BrdU method. ELISA was used to measure the levels of IFN-γ, IL-2, IL-4, IL-10, IL-12, and IL-17 cytokines, total IgG, as well as IgG1 and IgG2a subtypes in serum samples. Our findings showed that mice receiving the NLX/alum-adjuvanted vaccine exhibited increased antibody levels compared with other groups. In addition, there was a considerable difference in the levels of IgG1, IgG2a, IFN-γ, IL-2, IL-10, IL-12, and IL-17 in mice receiving the NLX/alum-adjuvanted vaccine as compared with other groups. The NLX/alum mixture, as an adjuvant, may have a positive effect on the induction of multi-cytokine responses as well as the increased level of IL-10, showing its higher immunogenicity with a higher immunoregulatory mechanism.

Determination of buprenorphine, norbuprenorphine, naloxone, and their glucuronides in urine by liquid chromatography-tandem mass spectrometry.

A liquid chromatography-tandem mass spectrometry method for the simultaneous quantification of buprenorphine (BUP), norbuprenorphine (NBUP), naloxone (NAL), and their glucuronide conjugates BUP-G, NBUP-G, and NAL-G in urine samples was developed. The method, omitting a hydrolysis step, involved non-polar solid-phase extraction, liquid chromatography on a C18 column, electrospray positive ionization, and mass analysis by multiple reaction monitoring. Quantification was based on the corresponding deuterium-labelled internal standards for each of the six analytes. The limit of quantification was 0.5μg/L for BUP and NAL, 1μg/L for NAL-G, and 3μg/L for NBUP, BUP-G, and NBUP-G. Using the developed method, 72 urine samples from buprenorphine-dependent patients were analysed to cover the concentration ranges encountered in a clinical setting. The median (maximum) concentration was 4.2μg/L (102 μg/L) for BUP, 74.7μg/L (580 μg/L) for NBUP, 0.9μg/L (85.5μg/L) for NAL, 159.5μg/L (1370 μg/L) for BUP-G, 307.5μg/L (1970 μg/L) for NBUP-G, and 79.6μg/L (2310 μg/L) for NAL-G.

Med Check: Naloxone and Opioid Overdose; Evekeo ODT and ADHD in Children; Theta Burst Protocol and Depressive Disorder; Brilaroxazine Phase 2 Trials

Back to table of contents Previous article Next article Med CheckFull AccessMed Check: Naloxone and Opioid Overdose; Evekeo ODT and ADHD in Children; Theta Burst Protocol and Depressive Disorder; Brilaroxazine Phase 2 TrialsTerri D’ArrigoTerri D’ArrigoSearch for more papers by this authorPublished Online:28 May 2021https://doi.org/10.1176/appi.pn.2021.6.14Higher Naloxone Dose Approved for Opioid OverdoseIn April the Food and Drug Administration (FDA) approved Kloxxado, a higher dosage of naloxone nasal spray for the emergency treatment of known or suspected opioid overdose. The newly approved product, developed by Hikma Pharmaceuticals, delivers 8 mg of naloxone into the nasal cavity. The FDA had previously approved 2 mg and 4 mg naloxone nasal spray products.The FDA approved Kloxxado based on previous findings about the safety and effectiveness of Narcan injection (naloxone hydrochloride) for treating opioid overdose. Hikma Pharmaceuticals also submitted its own safety and effectiveness data.“Over the last several years, the FDA has taken a number of steps to improve availability of naloxone products, including encouraging manufacturers to pursue approval of over-the-counter naloxone products; requiring drug manufacturers for all opioid pain relievers and medicines to treat opioid use disorder to add new recommendations about naloxone to the prescribing information; and extending the shelf life of naloxone nasal spray from 24 months to 36 months,” the agency said in a statement.Evekeo ODT Approved for ADHD in Young ChildrenIn April the FDA approved Evekeo ODT (amphetamine sulfate) by Arbor Pharmaceuticals for treating attention-deficit/hyperactivity disorder (ADHD) in patients aged 3 to 5 years. Evekeo ODT, a mixture of dextroamphetamine sulfate and levoamphetamine sulfate, was previously approved for treating ADHD in patients aged 5 to 17 years, with tablets ranging in dose from 5 mg to 20 mg. Evekeo ODT will be available in a new 2.5 mg orally disintegrating tablet for patients 3 to 5 years old. The recommended starting dose for patients in this age group is 2.5 mg daily, and a second dose may be administered after 4 to 6 hours.Evekeo ODT is a Schedule II controlled substance and comes with a boxed warning noting that central nervous systems stimulants have a high potential for abuse and dependence. The boxed warning advises health professionals to assess their patients’ risk of abuse and dependence before prescribing the drug, and to monitor patients for signs of abuse and dependence as therapy continues.Theta Burst Protocol Cleared for Treating Major Depressive DisorderBrainsWay announced in April that its Theta Burst protocol has been approved by the FDA for treating major depressive disorder. Theta Burst is a three-minute protocol that uses the company’s Deep Transcranial Magnetic Stimulation (Deep TMS) system. TMS uses magnetic fields to stimulate parts of the brain and activate neural pathways to improve symptoms of depression.In a study of 146 patients with major depressive disorder, patients treated with the three-minute protocol experienced reductions in depression scores similar to those who received the standard 20-minute sessions, the company said in a statement. The standard treatment protocol consists of 20-minute sessions five times a week for four to six weeks, followed by treatment twice a week for up to 12 weeks as needed for maintenance.Brilaroxazine Promising in Phase 2 TrialsReviva Pharmaceuticals’ investigational drug brilaroxazine appeared to be safe and effective for treating schizophrenia and schizoaffective disorder in a phase 2 clinical trial, the company announced in April.In the trial, 234 adults who had acute exacerbation of schizophrenia or schizoaffective disorder were randomized to receive either treatment with brilaroxazine or placebo for four weeks. The primary endpoint was reduction in total Positive and Negative Syndrome Scale (PANSS) from baseline to the end of the treatment. At the end of four weeks, the PANSS total score was reduced by 20 points in patients who took brilaroxazine, which the company said in a statement is a “statistically significant treatment difference from the placebo.” ■ ISSUES NewArchived

Microneedle-mediated transdermal delivery of naloxone hydrochloride for treatment of opioid overdose

Naloxone (NAL) is administered parenterally or intranasally for treating opioid overdose. The short duration of action of NAL calls for frequent re-dosing which may be eliminated by the development of a transdermal system. This study aimed to assess the effect of microneedles on improving the skin permeation of NAL hydrochloride. In vitro permeation of NAL across intact and microneedle-treated (Dr. Pen™ Ultima A6) porcine skin was evaluated. The effect of microneedle length and application duration, and donor concentration on NAL permeation were investigated. In-vitro in-vivo correlation of the permeation results was done to predict the plasma concentration kinetics of NAL in patients. In vitro passive permeation of NAL after 6 h was observed to be 8.25±1.06 µg/cm2. A 56- and 37-fold enhancement was observed with 500 and 250 µm needles applied for 1 min, respectively. Application of 500 µm MNs for 2 min significantly reduced the lag time to ~ 8 min and increasing the donor concentration for the same treatment group doubled the permeation (p < 0.05). Modeling simulations demonstrated the attainment of pharmacokinetic profile of NAL comparable to those obtained with the FDA-approved intramuscular and intranasal devices. Microneedle-mediated transdermal delivery holds potential for rapid and sustained NAL delivery for opioid overdose treatment.

High‐dose naloxone nasal spray approved

The Food and Drug Administration (FDA) last month approved a higher‐dose naloxone hydrochloride nasal spray product (KLOXXADO) to treat opioid overdose. The FDA had previously approved 2 mg and 4 mg naloxone nasal spray products; the new product is 8 mg. It is hoped that this will help counteract the effects of illicit fentanyl.

Effect of naloxone hydrochloride on β-EP, CD4+, CD8+, IL2, MMP-9 and S100-B levels in peripheral blood after traumatic brain injury in rats

Purpose: To study the influence of naloxone hydrochloride on traumatic brain injury (TBI).&#x0D; Methods: Three groups of rats were used: normal control, TBI, and TBI + naloxone hydrochloride groups (12 rats/group). In the control group, only the osseous foramen was opened. Rats in TBI group were intraperitoneally injected with normal saline, while the naloxone group received naloxone hydrochloride injection at the same time. Changes in peripheral blood β-EP, CD4+, CD8+, IL-2, and S100-B levels; and brain tissue MMP-9 were assessed.&#x0D; Results: The levels of β-EP in the TBI- and naloxone-treated rats were higher than control values, while levels of CD4+ in TBI and naloxone groups were significantly lower than those of control group (p &lt; 0.01). At every time point, CD8+ level in naloxone group was significantly lower than that in TBI group (p &lt; 0.01). Compared with control group, the levels of IL-2 in the TBI and naloxone groups were significantly lower. Higher levels of S100-B were seen in TBI- and naloxone-treated rats, relative to control value. In the naloxone group, MMP-9 expression was downregulated, when compared to the expression TBI rats (p &lt; 0.05).&#x0D; Conclusion: Naloxone hydrochloride reduces β-EP, alleviates inflammation, protects nerve cells and reduces brain injury in TBI rats. There is, thus, a potential to develop naloxone for the management of brain injury

A covalent poly(lactic acid) naloxone nanoparticle reduces fentanyl‐induced poisoning in rats

Accidental and deliberate exposure to fentanyl and related synthetic opioid analogs are the primary catalysts behind the exponential rise in opioid-related fatal overdose in the US and worldwide. These synthetic opioids are either misused or added as adulterants in counterfeit prescription opioid and non-opioid medications. Although the opioid antagonist naloxone (NLX) is very effective at reversing opioid overdose, multiple doses of NLX may need to be administered to avoid renarcotization and death due to the apparent rapid metabolism of NLX compared to synthetic opioids. To circumvent this shortcoming of NLX and provide greater protection against overdose, this study developed covalent poly(lactic acid-co-glycolic acid) naloxone nanoparticle (NP-NLX) as a delivery platform for sustained-release of naloxone. In the current study, rats were exposed to repeated subcutaneous challenges of fentanyl at 0, 4, 24, and 48 hr timepoints and tested for respiratory depression via oximetry and antinociception via the hotplate test of central analgesia. Immediately following testing only after the t=0 hr timepoint, rats were rescued using either NLX or NP-NLX and tested 15 minutes later on the oximeter and hotplate. During all subsequent timepoints, rats did not receive NLX or NP-NLX. Data showed that NP-NLX was as effective as NLX at reversing fentanyl-induced effects 15 minutes after the initial fentanyl exposure. However, no effect of fentanyl was seen during subsequent fentanyl treatments due to the establishment of tolerance. To circumvent fentanyl-induced tolerance and to demonstrate efficacy at later timepoints, an independent follow-up study involved rats receiving NLX or NP-NLX 0 hr, but not fentanyl. Fentanyl challenges at subsequent timepoints showed that NP-NLX protected against fentanyl effects during the 4 and 24 hr timepoints, while NLX did not. These results suggest that NP-NLX could be an effective alternative to NLX to reverse fentanyl-induced overdose and prevent renarcotization, and that covalent poly(lactic acid-co-glycolic acid) nanoparticles are an attractive delivery platform for opioid antagonists or other small molecules used in treatment of toxicity.

Naltrindole Exhibits Robust Cardioprotection in Myocardial Ischemia Reperfusion Injury

The predominant opioid receptor subtypes in heart tissue are delta and kappa opioid receptors. Activation of delta and kappa opioid receptors during preconditioning have been shown to reduce infarct size in myocardial ischemia reperfusion (I/R) injury. This cardioprotective effect has been abolished with naloxone (NX), a broad-spectrum opioid receptor antagonist (e.g., delta, kappa, and mu). Previously, we demonstrated that a novel tripeptide, structurally similar to other delta or kappa opioid peptide receptor agonists, when given prior to global ischemia, significantly reduced infarct size and improved post-reperfused cardiac function using a Langendorf rat I/R heart ex vivo model. To identify the opioid receptor subtype responsible for tripeptide's cardioprotective effects, we used naltrindole (NTI), a selective delta opioid receptor antagonist. The cardioprotective effects of tripeptide were blocked by NX, but not NTI. To determine whether the cardioprotective effects of the combination was due to tripeptide or NTI, the effects of NTI and NX were evaluated individually in the same model. Male Sprague-Dawley rats (~300g) were subjected to global I(30min)/R(50min). NX (10 μM, n=6) or NTI (5 μM, n=8) or H2O vehicle (control n= 10) were given to hearts 5 min prior to ischemia and during the first 5 min of reperfusion in a Langendorf perfused model. Left ventricular (LV) cardiac function indices were measured using a pressure transducer. At the end of reperfusion (50min), hearts were frozen, sectioned (2 mm), and stained with 1% triphenyltetrazolium chloride (TTC). Infarcted heart tissue was compared to total tissue weight. Data were evaluated using ANOVA Student-Newman-Keuls post-hoc analysis. Control hearts (n=10) exhibited increased final LV end diastolic pressure (LVEDP) of 60±5 mmHg from baseline values (~8mmHg for all groups) and a mean infarct size of 36 ± 3% at 50 min post-reperfusion. NX showed no significant cardioprotective effect, since final LVEDP (64 ± 5%) and infarct size (35 ± 5%) was similar to control hearts. Surprisingly, the selective delta opioid antagonist, NTI, remarkably improved final LVEDP to 17 ± 3mmHg to near baseline values and reduced infarct size to 7 ± 2% compared to control and NX hearts (both p<0.01). The results indicate that NTI can prevent ischemic injury and restore post-reperfused heart function to pre-ischemic levels. In future studies, we will examine the intracellular mechanisms of NTI responsible for preventing myocardial ischemic injury.

Activation of Oxytocin Receptors and Oxytocin Neurons of the Hypothalamic Paraventricular Nucleus Are Individually Capable of Reversing Opioid Overdose

Opioid-induced respiratory depression (OIRD) can result in fatal respiratory arrest. The current gold standard for intervention is opioid displacement using high affinity opioid receptor antagonists, like naloxone (NLX), which reverse OIRD and, undesirably, opioid analgesia. We recently reported in rats that the most lethal clinically used opioid fentanyl (60 nmol/kg, i.v.) causes OIRD that is reversed by systemic NLX (2.5 µmol/kg, i.v.). Multiple reports indicate that systemic NLX rapidly triggers release of the analgesic neuropeptide oxytocin (OXTN) from the hypothalamic paraventricular nucleus (PVN) both in opioid-dependent and opioid-naïve rats. Given that OXTN microinjections into specific nodes of the respiratory network can stimulate breathing, we hypothesized that OXTN can reverse fentanyl OIRD. We recorded phrenic nerve activity (PNA) to index neural inspiration in anesthetized (urethane/chloralose), vagotomized, paralyzed and artificially ventilated rats and determined that systemic peptide and non-peptide activation of OXTN receptors robustly reversed PNA arrest by fentanyl (60 nmol/kg, i.v.) (P<0.0001, n=4-6). Because nearly all systemic NLX-induced OXTN release is from the PVN, we tested the possibility that PVN NLX could counteract OIRD.PVN NLX (3 nmol/kg, 50 nL) not only reversed PNA arrest by fentanyl (60 nmol/kg, i.v.) (P=0.0238, n=3), but prevented it altogether (P=0.0107, n=3-4). To determine whether direct stimulation of PVN OXTN neurons could reverse fentanyl OIRD, we used an optogenetic approach. Mice with channelrhodopsin selectively expressed in OXTN neurons were anesthetized (ketamine-acepromazine-xylazine) and instrumented with arterial and venous catheters along with an optical fiber cannula dorsal to PVN. While spontaneously breathing, expired CO2 was used to monitor rhythmic ventilation and to quantify bradypnea during OIRD. Following systemic fentanyl (60 nmol/kg, i.v.), blue light (473 nm, 12 mW) pulses (10 ms, 20 Hz) were delivered to the PVN using a 5 s On/1 s Off pattern for 3 min. Photo-stimulation, which did not stimulate basal respiration rate (P=0.9056), prevented lethal effects of fentanyl OIRD (P<0.0001, n=3). Whereas dummy pulses during fentanyl OIRD permitted apneas as long as 51.1±16.5 s and proved to be lethal, optogenetic stimulation significantly attenuated apneas to a maximum 2.9±1.6 s (P<0.0001) and resulted in respiratory rate progressively recovering to 60.7±0.4% of baseline by the end of photo-stimulation. Although the expired CO2 increase post-fentanyl was similar (P=0.0334-P<0.0001) prior to PVN photo-stimulation between cohorts receiving blue light and dummy pulses (P=0.2171), the latter failed to prevent lethal respiratory arrest (P<0.0001). Findings indicate that systemic treatment with OXTN receptor agonists and activation of PVN OXTN neurons, both previously demonstrated to be analgesic, can reverse fentanyl overdose in rodents without requiring analgesia-reversing opioid receptor antagonism.

Influence of different kinds of stress on apoptosis of CD4&lt;sup&gt;+&lt;/sup&gt;/CD8&lt;sup&gt;+&lt;/sup&gt; lymphocytes upon &lt;i&gt;in vivo&lt;/i&gt; blockage of opiate receptors

The endogenous opioid system is involved in regulation of many body functions, including immune system regulation. Endogenous opioid peptides are released under stress and communicate with opiate receptors, which are found on most immune cells. Apoptosis is one of the most important instruments in the regulation of the immune system. The aim of this study was to evaluate effects of various types of stress upon apoptosis of CD4+/ CD8+ lymphocytes under conditions of opiate receptor blockade. The objects of this study were white outbred male mice, been kept in laboratory vivarium. The following types of stress were studied: immobilization (6 h in the supine position), rotational (60 min: 10 min rotation at 78 rpm, 5 min rest), two types of acute cold (10 min or 60 min at -20 °С), chronic cold (-4 °С for 4 hours daily, for 7 days). Opiate receptors have been blocked by subcutaneous administration of naloxone hydrochloride at a dose of 0.2 mg/kg 20 minutes before stress, and again 3 hours later, with a stress duration of over 3 hours. Splenocytes were stained with PE-labeled monoclonal antibodies against murine CD4, and antibodies against mouse CD8 (BioLegent, USA); after incubation and washing, they were stained with reagents for determining apoptosis. V-FITC / 7-AAD annexin kit (Beckman Coulter, USA) according to the manufacturer's instructions. Lymphocyte apoptosis was recorded with a CytoFLEX S cytometer (Beckman Coulter, USA). Results. It was found that immobilization stress (lasting 6 h) and acute cold stress (60 min -20 °С), regardless of naloxone administration, enhance apoptosis of mouse CD8+ lymphocytes. Chronic cold stress (-4 °С 4 hours / 7 days) led to a decrease in apoptotic spleen lymphocyte numbers only during the blockade of opiate receptors. The effects of rotational stress and short-term acute cold stress (-20 °С, 10 min) upon apoptosis were not registered. Thus, two types of stress (immobilization and acute cold) caused intensification of CD8+ lymphocyte apoptosis; endogenous opioid system seems not to participate in regulation of these processes. Under conditions of chronic cold stress with naloxone injections, we have noted a decreased Annexin binding by spleen lymphocytes in mice.

Intoxication in a pig (Sus scrofa domesticus) after transdermal fentanyl patch ingestion : case report

An experimental study on the effects of electroporation on pancreatic tissue was performed in pigs, and the fentanyl transdermal patch (FTP) was used postoperatively as part of multimodal pain management. Ingestion of an FTP, which resulted in fentanyl intoxication, was suspected 5 days after placement in one of the experimental pigs. The pig was first dysphoric, running in the stall, panting and vocalizing until it finally became depressed and it remained lying on the floor. Ingestion of an FTP was not observed but the fentanyl plasma concentration on the day of intoxication was 20.7 ng/ml, while at its peak after FTP administration it was only 0.492 ng/ml. The intoxication was successfully treated with a single intramuscular naloxone injection.

The Role of the Social Network in Fatal Opioid Overdose Prevention: The Former Opioid User’s Perspective

Naloxone hydrochloride (naloxone) is an effective fatal opioid overdose prevention strategy. The study findings describe former opioid users’ phenomenological perspectives regarding their social network, settings of use, and the benefits and barriers to naloxone. Participants ( N = 25) with at least 6 months of recovery time ( M = 30, SD = 14.40) were interviewed individually for an average of 21 ( SD = 5.13) min. The sample was predominately male, Caucasian, and non-Hispanic with an average age of 37 ( SD = 7.22) years. Interview transcripts were analyzed using systematic thematic analysis. During their period of opioid use, most participants differentiated the members of their social network as other people who use opioids (PWUO) and nonusers. The participants described several opportunities for members of their social network to use naloxone. They discussed barriers to naloxone use specific to PWUO within their social network such as apathy toward overdose. Future interventions should be tailored to address naloxone use barriers specific to PWUO and nonusers.

A Molecularly Imprinted Sol-Gel Electrochemical Sensor for Naloxone Determination.

A molecularly imprinted sol-gel is reported for selective and sensitive electrochemical determination of the drug naloxone (NLX). The sensor was developed by combining molecular imprinting and sol-gel techniques and electrochemically grafting the sol solution onto a functionalized multiwall carbon nanotube modified indium-tin oxide (ITO) electrode. The sol-gel layer was obtained from acid catalyzed hydrolysis and condensation of a solution composed of triethoxyphenylsilane (TEPS) and tetraethoxysilane (TES). The fabrication, structure and properties of the sensing material were characterized via scanning electron microscopy, spectroscopy and electrochemical techniques. Parameters affecting the sensor’s performance were evaluated and optimized. A sensor fabricated under the optimized conditions responded linearly between 0.0 µM and 12 µM NLX, with a detection limit of 0.02 µM. The sensor also showed good run-to-run repeatability and batch-to-batch performance reproducibility with relative standard deviations (RSD) of 2.5–7.8% (n = 3) and 9.2% (n = 4), respectively. The developed sensor displayed excellent selectivity towards NLX compared to structurally similar compounds (codeine, fentanyl, naltrexone and noroxymorphone), and was successfully used to measure NLX in synthetic urine samples yielding recoveries greater than 88%.

Acute toxicity, anti-inflammatory and antinociceptive investigations of extracts from Ampelocissus africana (Lour) Merr (Vitaceae) rhizomes

Ampelocissus africana (Lour) Merr (Vitaceae) is a plant used in traditional medicine in Burkina Faso in the treatment of wounds, edema, drops, infections. This study focused on pharmacological investigations effects of methanolic and aqueous extracts from Ampelocissus africana (Lour) Merr rhizomes. The acute toxicity of the extracts from Ampelocissus africana was performed under OECD 423 guidelines. The anti-inflammatory activity was evaluated in vivo using carrageenan-induced paw edema of mice at the doses to 50, 100, 200, 400, 600 mg/kg body weight (bw). The antinociceptive activity of the extracts was determined using acetic acid, formalin nociception models in mice at the doses to 50, 100, 200, 400 and 600 mg/kg bw. The involvement of ATP-sensitive K + channel pathway and opioid system were tested using glibenclamide, and naloxone respectively at the unique dose (400 mg/kg). No mortality of mice were observed at dose of 2000 mg/kg b.w. The lethal dose (LD 50 ) value estimated to 5000 mg/kg b.w. The tests were showed that the extracts exerted significant dose-dependent anti-inflammatory responses in the paw induced by carrageenan (from 37 to 72.90 percent inhibition), antinociceptives in acetic-induced abdominal contractions (from 25.10 to 63.08%), and in formaldehyde-induced paw licking (from 9.27 to 71.77%) tests. The pretreatment with naloxone and glibenclamide did not affect the antinociceptives effects. The results suggested that the extracts from the rhizomes of Ampelocissus africana possessed anti-inflammatory and antinociception effects in mice. These effects could justify the uses of this plant in traditional medicine.

Subsequent opioid overdose resulting in death in individuals in Allen County, Indiana who receive naloxone administration for past opioid overdose

Background and Hypothesis: &#x0D; Over-prescription of opioids has contributed to increases in opioid overdose (OOD) and OOD deaths. Studies suggest recurring OODs in an individual could be contributing. After a non-fatal overdose, one study found 7% of patients continued to abuse opioids and had another OOD within 1 year. Additionally, the literature suggests a positive correlation between non-fatal overdose and increased risk of subsequent overdose death. Allen County has also experienced increases in overdoses and overdose deaths. We aim to isolate opioid-specific overdoses and deaths in Allen County from current overdose data. We hypothesize individuals in Allen County who received naloxone for OOD have an increased risk of death from a subsequent OOD. An additional objective is to utilize data from the county ambulance service and the two major Allen County health systems to gain more accurate and current accountings of the OOD data. &#x0D; &#x0D; Methods: &#x0D; This study is a retrospective case-control using electronic medical records and/or electronic patient care reports from the Three Rivers Ambulance Authority, Parkview Health, and Lutheran Health Network. Patients who received naloxone between 2018-2020 will be divided into a case group of individuals who died of OOD and a control group of living individuals. Demographics and naloxone administrations data per subject will be collected. Box-and-whisker plots, a Mann-Whitney U Test, and a Wilcoxon matched-pairs signed rank test will be done for comparisons. &#x0D; &#x0D; Results and Conclusion: &#x0D; This project has resulted in a study protocol ready for IRB submission with IRB approval and study start date anticipated for Summer 2021. &#x0D; &#x0D; Potential Impact: &#x0D; This study will add to existing knowledge on OOD and subsequent OOD death. Specifically, this study will provide more accurate and current accountings of the OOD data that may aid in the development of policy and interventions to reduce the local opioid crisis.

ANESTHESIA AND SURGERY PROTOCOLS FOR INTRA-ABDOMINAL TRANSMITTER PLACEMENT IN FOUR SPECIES OF WILD ARMADILLO.

The anatomy and physiology of armadillos make anesthetic procedures and the placement of telemetry devices challenging. From June 2011 to November 2019, a total of 73 free-living armadillos were captured and anesthetized in the Pantanal, Brazil. Giant (Priodontes maximus), six-banded (Euphractus sexcinctus), southern naked-tailed (Cabassous unicinctus), and nine-banded (Dasypus novemcinctus) armadillos were divided into two groups. In group 1, 30 armadillos were anesthetized for collection of biological samples, body measurements, and placement of a microchip tag. Anesthetic combination BDM was applied: butorphanol tartrate, detomidine hydrochloride, and midazolam hydrochloride, each at 0.1 mg/kg. In group 2, 43 armadillos received ketamine hydrochloride at 10 mg/kg 20 min after BDM injection, and intra-abdominal radio transmitters were surgically implanted. The transmitter was inserted freely into the abdominal cavity. Vital signs were monitored during anesthesia every 10 min and varied within species and between groups. Rectal temperature varied from 33.1 ± 1.36 to 35.34 ± 1.21°C, heart rate (beats/min) from 19 ± 2.14 to 84.71 ± 9.25, respiratory rate (breaths/min) from 11 ± 4.16 to 31 ± 2.82, and oxygen saturation values (SPO2%) from 84.17% ± 2.39 to 98% ± 1.20. Both groups received the antagonist combination NYF: naloxone hydrochloride (0.02 mg/kg), yohimbine hydrochloride (0.125 mg/kg), and flumazenil (0.01 mg/kg). Recovery varied according to intravenous or intramuscular injection from 2 ± 4 to 8.08 ± 2.93 min respectively. BDM protocol was considered satisfactory and provided enough time to complete the procedures (60 ± 85 to 133.20 ± 9.12 min) according to the species and group. Ketamine added to the BDM provided enough time and a surgical plane of anesthesia (97 ± 22 to 137 ± 39.5 min). The surgical procedure technique chosen did not appear to have a negative impact on armadillos studied. Implantable transmitters provide a cost-effective method for long-term monitoring of wild individuals.

Physical Compatibility and Chemical Stability of Fentanyl and Naloxone Hydrochloride in 0.9% Sodium Chloride Injection Solution for Patient-Controlled Analgesia Administration.

Background and ObjectiveThe combination of naloxone hydrochloride (NH) and fentanyl citrate (FC) in patient-controlled analgesia (PCA) is examined to reduce the risk of opioid-induced nausea and vomiting. However, there are no such commercially available drug mixtures, and there is also no published evidence on the compatibility and stability of NH and FC. Thus, the primary purpose of the current research is to investigate the physical compatibility and chemical stability of NH when mixed with FC over a 72-h period in a 0.9% sodium chloride injection solution for PCA administration under storage at 4°C and 25°C.MethodsTest solutions of 20 μg/mL FC and 4 μg/mL NH were prepared and stored in polyvinyl chloride (PVC) bags or glass bottles with a 0.9% sodium chloride injection solution as the diluent. During the 72-h storage period at 4°C or 25°C without light protection, the concentrations of the test drugs were assayed via high-performance liquid chromatography (HPLC), and the physical compatibility was determined with the naked eye. Furthermore, pH measurement of each sample was also performed with a pH meter.ResultsThe percentages of the initial concentrations of FC and NH in the various solutions were maintained at a minimum of 98% over the 72-h study period. All of the mixtures remained clear and colourless throughout the observation period, and no precipitation or turbidity was observed in any of the batches.ConclusionThe 20 μg/mL FC test solution was physically compatible and chemically stable with the 4 μg/mL NH test solution when stored at 4°C or 25°C in PVC bags or glass bottles containing the 0.9% sodium chloride injection solution.