Motivation and context of concurrent stimulant and opioid use among persons who use drugs in the rural United States: a multi-site qualitative inquiry.

BACKGROUND: In recent years, stimulant use has increased among persons who use opioids in the rural U.S., leading to high rates of overdose and death. We sought to understand motivations and contexts for stimulant use among persons who use opioids in a large, geographically diverse sample of persons who use drugs (PWUD) in the rural settings. METHODS: We conducted semi-structured individual interviews with PWUD at 8 U.S. sites spanning 10 states and 65 counties. Content areas included general substance use, injection drug use, changes in drug use, and harm reduction practices. We used an iterative open-coding process to comprehensively itemize and categorize content shared by participants related to concurrent use. RESULTS: We interviewed 349 PWUD (64% male, mean age 36). Of those discussing current use of stimulants in the context of opioid use (n = 137, 39%), the stimulant most used was methamphetamine (78%) followed by cocaine/crack (26%). Motivations for co-use included: 1) change in drug markets and cost considerations; 2) recreational goals, e.g., seeking stronger effects after heightened opioid tolerance; 3) practical goals, such as a desire to balance or alleviate the effects of the other drug, including the use of stimulants to avoid/reverse opioid overdose, and/or control symptoms of opioid withdrawal; and 4) functional goals, such as being simultaneously energized and pain-free in order to remain productive for employment. CONCLUSION: In a rural U.S. cohort of PWUD, use of both stimulants and opioids was highly prevalent. Reasons for dual use found in the rural context compared to urban studies included changes in drug availability, functional/productivity goals, and the use of methamphetamine to offset opioid overdose. Education efforts and harm reduction services and treatment, such as access to naloxone, fentanyl test strips, and accessible drug treatment for combined opioid and stimulant use, are urgently needed in the rural U.S. to reduce overdose and other adverse outcomes.

Substance use patterns, sociodemographics, and health profiles of harm reduction service recipients in Burlington, Vermont.

BACKGROUND: Understanding current substance use practices is critical to reduce and prevent overdose deaths among individuals at increased risk including persons who use and inject drugs. Because individuals participating in harm reduction and syringe service programs are actively using drugs and vary in treatment participation, information on their current drug use and preferred drugs provides a unique window into the drug use ecology of communities that can inform future intervention services and treatment provision. METHODS: Between March and June 2023, 150 participants in a harm reduction program in Burlington, Vermont completed a survey examining sociodemographics; treatment and medication for opioid use disorder (MOUD) status; substance use; injection information; overdose information; and mental health, medical, and health information. Descriptive analyses assessed overall findings. Comparisons between primary drug subgroups (stimulants, opioids, stimulants-opioids) of past-three-month drug use and treatment participation were analyzed using chi-square and Fisher's exact test. RESULTS: Most participants reported being unhoused or unstable housing (80.7%) and unemployed (64.0%) or on disability (21.3%). The drug with the greatest proportion of participants reporting past three-month use was crack cocaine (83.3%). Fentanyl use was reported by 69.3% of participants and xylazine by 38.0% of participants. High rates of stimulant use were reported across all participants independent of whether stimulants were a participant's primary drug. Fentanyl, heroin, and xylazine use was less common in the stimulants subgroup compared to opioid-containing subgroups (p < .001). Current- and past-year MOUD treatment was reported by 58.0% and 77.3% of participants. Emergency rooms were the most common past-year medical treatment location (48.7%; M = 2.72 visits). CONCLUSIONS: Findings indicate high rates of polysubstance use and the underrecognized effects of stimulant use among people who use drugs-including its notable and increasing role in drug-overdose deaths. Crack cocaine was the most used stimulant, a geographical difference from much of the US where methamphetamine is most common. With the increasing prevalence of fentanyl-adulterated stimulants and differences in opioid use observed between subgroups, these findings highlight the importance and necessity of harm reduction interventions (e.g., drug checking services, fentanyl test strips) and effective treatment for individuals using stimulants alongside MOUD treatment.

Modeling Developmental Changes in Caffeine Clearance Considering Differences between Pre- and Postnatal Period.

Taguchi et al. reported that postmenstrual age (PMA) is a promising factor in describing and understanding the developmental change of caffeine (CAF) clearance. The aim of the present study was to quantify how developmental changes occur and to determine the effect of the length of the gestational period on CAF clearance. We performed a nonlinear mixed effect model (NONMEM) analysis and evaluated the fit of six models. A total of 115 samples were obtained from 52 patients with a mean age of 34.3 ± 18.2 d. The median values of gestational age (GA) and postnatal age (PNA) were 196 and 31 d, respectively. Serum CAF levels corrected for dose per body surface area (BSA) (C/D ratioBSA) were dependent on PMA rather than PNA, which supports the findings of a previous study. NONMEM analysis provided the following final model of oral clearance: CL/F = 0.00603∙WT∙∙0.877GA ≤ 196 L/h. This model takes into account developmental changes during prenatal and postnatal periods separately. The model successfully described the variation in clearance of CAF. Our findings suggest that the dosage of CAF in preterm infants should be determined based not only on body weight (WT) but also on both PNA and GA.

Psychosis with use of amphetamine drugs, methylphenidate and atomoxetine in adolescent and adults.

BACKGROUND: Use of psychostimulants and relative drugs has increased worldwide in treatment of attention-deficit hyperactivity disorder (ADHD) in adolescents and adults. Recent studies suggest a potential association between use of psychostimulants and psychotic symptoms. The risk may not be the same between different psychostimulants. OBJECTIVE: To assess whether amphetamine or atomoxetine use is associated with a higher risk of reporting symptoms of psychosis than methylphenidate use in adolescents and adults, particularly in patients with ADHD. METHODS: Using VigiBase, the WHO's pharmacovigilance database, disproportionality of psychotic symptoms reporting was assessed among adverse drug reactions related to methylphenidate, atomoxetine and amphetamines, from January 2004 to December 2018, in patients aged 13-25 years. The association between psychotic symptoms and psychostimulants was estimated through the calculation of reporting OR (ROR). FINDINGS: Among 13 863 reports with at least one drug of interest, we found 221 cases of psychosis with methylphenidate use, 115 with atomoxetine use and 169 with a prescription of an amphetamine drug. Compared with methylphenidate use, amphetamine use was associated with an increased risk of reporting psychotic symptoms (ROR 1.61 (95% CI 1.26 to 2.06)]. When we restricted the analysis to ADHD indication, we found a close estimate (ROR 1.94 (95% CI 1.43 to 2.64)). No association was found for atomoxetine. CONCLUSION: Our study suggests that amphetamine use is associated with a higher reporting of psychotic symptoms, compared with methylphenidate use. CLINICAL IMPLICATIONS: The prescription of psychostimulants should consider this potential adverse effect when assessing the benefit-risk balance.

Fetal alcohol spectrum disorder and attention deficit hyperactivity disorder stimulant trial in children: an N-of-1 pilot trial to compare stimulant to placebo (FASST): protocol.

INTRODUCTION: Fetal alcohol spectrum disorder (FASD) is a neurodevelopmental disorder caused by alcohol exposure during pregnancy. FASD is associated with neurodevelopmental deviations, and 50%-94% of children with FASD meet the Diagnostic and Statistical Manual of Mental Disorders-fifth edition diagnostic criteria for attention deficit hyperactivity disorder (ADHD). There is a paucity of evidence around medication efficacy for ADHD symptoms in children with FASD. This series of N-of-1 trials aims to provide pilot data on the feasibility of conducting N-of-1 trials in children with FASD and ADHD. METHODS AND ANALYSIS: A pilot N-of-1 randomised trial design with 20 cycles of stimulant and placebo (four cycles of 2-week duration) for each child will be conducted (n=20) in Melbourne, Australia.Feasibility and tolerability will be assessed using recruitment and retention rates, protocol adherence, adverse events and parent ratings of side effects. Each child's treatment effect will be determined by analysing teacher ADHD ratings across stimulant and placebo conditions (Wilcoxon rank). N-of-1 data will be aggregated to provide an estimate of the cohort treatment effect as well as individual-level treatment effects. We will assess the sample size and number of cycles required for a future trial. Potential mediating factors will be explored to identify variables that might be associated with treatment response variability. ETHICS AND DISSEMINATION: The study was approved by the Hospital and Health Service Human Research Ethics Committee (HREC/74678/MonH-2021-269029), Monash (protocol V6, 25 June 2023).Individual outcome data will be summarised and provided to participating carers and practitioners to enhance care. Group-level findings will be presented at a local workshop to engage stakeholders. Findings will be presented at national and international conferences and published in peer-reviewed journals. All results will be reported so that they can be used to inform prior information for future trials. TRIAL REGISTRATION NUMBER: NCT04968522.

A critical review of the dextroamphetamine transdermal system for the treatment of ADHD in adults and pediatric patients.

INTRODUCTION: The dextroamphetamine transdermal system (d-ATS) is a stimulant patch recently approved by the United States (U.S.) Food and Drug Administration for the treatment of attention-deficit/hyperactivity disorder (ADHD). AREAS COVERED: The composition of the d-ATS, pharmacokinetics, and metabolism are presented along with data from dermal trials evaluating the tolerability of patch application at various skin sites. Efficacy and safety data from a laboratory classroom study in children and adolescents including effect sizes are assessed. Pharmacokinetic-pharmacodynamic modeling of variable wear times is also discussed. EXPERT OPINION: Although stimulants are recommended as first-line treatment for ADHD in the U.S. some patients may have difficulty swallowing intact tablets and capsules, or dislike the taste or texture of chewable, oral disintegrating, or liquid formulations. The d-ATS fills an unmet need for those with ADHD who are unable or prefer not to take medication orally. Varying wear time of the d-ATS also gives flexibility in length of stimulant effect which may be useful for patients with changing schedules. However, dermal discomfort must be considered in addition to the usual amphetamine side effects when prescribing the d-ATS. Patient and provider experience will determine how frequent the use of d-ATS becomes.

[Wakefulness-promoting agents for severe fatigue: to use or not to use?] / Medicatie tegen ernstige aanhoudende vermoeidheid.

About 20% of adults experience excessive daytime sleepiness or severe fatigue. Causes include somatic conditions, psychiatric disorders, and medication or drug use. Treatment depends on the underlying cause. If sleepiness persists despite optimal treatment of the underlying condition, exclusion of other causes, and behavioral interventions, wakefulness-promoting agents may be considered. However, no established pharmacological strategy exists for symptomatic treatment. Modafinil and stimulants like methylphenidate may offer some benefit based on experiences with narcolepsy or idiopathic hypersomnia. Studies in specific patient groups (e.g., multiple sclerosis, Parkinson's disease, traumatic brain injury, cancer-related fatigue) show variable results. The use of wakefulness-promoting agents is discouraged for addressing unexplained fatigue, as seen in the context of chronic fatigue syndrome.

Stigma Related to the Non-Medical Use and Diversion of Prescription Stimulant Drugs: Should We Care.

BACKGROUND: Non-medical use (NMU) and diversion of prescription stimulants are prevalent on college campuses. Diversion represents a primary source of acquisition for NMU among young adults. This study examined relationships between stigmatizing beliefs related to NMU and diversion of stimulant medications and engagement in these behaviors, as well as how such perceptions are associated with indicators of psychological distress among those who engage in these behaviors. METHODS: Young adults (N = 384) were recruited from a large US university to participate in this cross-sectional electronic survey-based study. Relationships between stigma variables and NMU and diversion were assessed. Among those who engage in NMU and diversion, we tested relationships between stigma variables and indicators of psychological distress, using validated instruments. RESULTS: Perceived social and personal stigmatic beliefs did not significantly predict NMU. However, perceived social and personal stigma of diversion significantly reduced diversion likelihood. For NMU, associations were found between stigma variables and indicators of psychological distress. Markedly, we found that as stigmatic perceptions of NMU increased, so did depressive, anxiolytic, and suicidal symptomatology among those who engage in NMU. CONCLUSIONS: Stigmatization does not deter NMU; however, stigmatization is positively associated with psychological harm among those who engage in NMU. Interventions should be developed to reduce stigmatization in order to improve psychological health among those who engage in NMU. Stigmatic perceptions of diversion were not predictive of psychological harm, though they are negatively associated with diversion behavior.

Patterns of Psychiatric Medication Prescriptions for Veterans in Treatment Courts and Other Specialty Courts.

Psychiatric medications can serve as important tools for addressing behavioral health issues among criminal justice-involved (CJI) veterans. This study used national data on 12,790 CJI veterans in the U.S. Department of Veterans Affairs (VA) Veterans Justice Outreach program from 2019 to 2020 to compare patterns of psychiatric medication prescriptions among veterans who entered a veterans treatment court (n = 6975), another specialty court (SC; n = 414), or no-SC (n = 5401). Different classes of medications were examined, including antidepressants, stimulants, antipsychotics, benzodiazepines, and medications for substance use disorders. The results showed that 60.2% of the total sample was prescribed a psychiatric medication within 1 year of entering the Veterans Justice Outreach program. There was no significant difference in overall psychiatric prescribing among veterans treatment court, other SC, and no-SC groups, but there were a few differences in certain classes of psychiatric medications. Moreover, about 7.8% of veterans who were in the no-SC group and were prescribed psychiatric medications did not have a psychiatric diagnosis. Veterans who were younger, non-Hispanic white, married, with a VA service-connected disability rating, had a diagnosis of mental and/or substance use disorder, and used more VA health care services were more likely to have been prescribed psychiatric medication. Together, these findings illustrate the essential role of psychiatric medications in courts and programs that serve CJI veterans, as well as the important link between VA service engagement and psychiatric prescriptions.

Changes in real-world dispensing of ADHD stimulants in youth from 2019 to 2021 in California.

Introduction: Attention-deficit/hyperactivity disorder (ADHD) is one of the most common pediatric neurobehavioral disorders in the U.S. Stimulants, classified as controlled substances, are commonly used for ADHD management. We conducted an analysis of real-world stimulants dispensing data to evaluate the pandemic's impact on young patients (≤ 26 years) in California. Methods: Annual prevalence of patients on stimulants per capita across various California counties from 2019 and 2021 were analyzed and further compared across different years, sexes, and age groups. New patients initiating simulants therapy were also examined. A case study was conducted to determine the impact of socioeconomic status on patient prevalence within different quintiles in Los Angeles County using patient zip codes. Logistic regression analysis using R Project was employed to determine demographic factors associated with concurrent use of stimulants with other controlled substances. Results: There was a notable reduction in prevalence of patients ≤26 years old on stimulants during and after the pandemic per 100,000 people (777 in 2019; 743 in 2020; 751 in 2021). These decreases were more evident among the elementary and adolescent age groups. The most prevalent age group on stimulants were adolescents (12-17 years) irrespective of the pandemic. A significant rise in the number of female patients using stimulants was observed, increasing from 107,957 (35.2%) in 2019 to 121,241 (41.1%) in 2021. New patients initiating stimulants rose from 102,754 in 2020 to 106,660 in 2021, with 33.2% being young adults. In Los Angeles County, there was an increasing trend in patient prevalence from Q1 to Q5 income quintiles among patients ≥6 years. Consistently each year, the highest average income quintile exhibited the highest per capita prevalence. Age was associated with higher risk of concurrent use of benzodiazepines (OR, 1.198 [95% CI, 1.195-1.201], p < 0.0001) and opioids (OR, 1.132 [95% CI, 1.130-1.134], p < 0.0001) with stimulants. Discussion: Our study provides real-world information on dispensing of ADHD stimulants in California youth from 2019 to 2021. The results underscore the importance of optimizing evidence-based ADHD management in pediatric patients and young adults to mitigate disparities in the use of stimulants.

Evaluating cross-reactivity of new psychoactive substances (NPS) in human whole blood by enzyme-linked immunosorbent assay (ELISA).

Due to the increase in the use of novel psychoactive substances (NPS) and their overall prevalence, it is important to have effective and reliable screening technologies to detect NPS in biological matrices. Enzyme-linked immunosorbent assays (ELISA) are among the most popular screening methods. To evaluate the effectiveness of ELISA for NPS detection, five subclasses of NPS (novel synthetic opioids, fentanyl analogs, stimulants, benzodiazepines and hallucinogens) were evaluated in whole blood for their cross-reactivity on commercially available ELISA kits. A variety of novel synthetic opioids were tested at concentrations of 1-80 ng/mL and 50-2000 ng/mL and demonstrated no cross-reactivity to a morphine ELISA plate at either concentration range. Fentanyl analogs were tested at concentrations ranging from 0.01 to 1 ng/mL and had cross-reactivities ranging from 8% to 178% on the fentanyl ELISA kit used. Both para-chloro fentanyl (178%) and acryl fentanyl (164%) showed cross-reactivities well above that of fentanyl. Novel stimulants were tested at concentrations of 0.5-40 ng/mL and 20-2,000 ng/mL. 4-Fluoroamphetamine was the only novel stimulant with cross-reactivity (3,354%) to the amphetamine ELISA plate. Novel benzodiazepines were tested at concentrations of 1-40 ng/mL on a benzodiazepine plate. Cross-reactivities ranged from 36.1% to 263%, with desalkylflurazepam having the highest cross-reactivity. Finally, novel hallucinogens were tested at concentrations of 0.5-10 ng/mL on a phencyclidine (PCP) ELISA plate, which produced no cross-reactivity and then with 10-1,000 ng/mL, which gave results from 56.6% to 151%. Both hydroxy-PCP (151%) and chloro-PCP (137%) showed cross-reactivities above that of PCP. This research has demonstrated the utility of using ELISA-based screening for novel benzodiazepines, hallucinogens and for fentanyl analogs; however, there is limited application and risk of false-negative results for the other drug classes due to low or non-existent cross-reactivities.

Treatments for ADHD in Children and Adolescents: A Systematic Review.

CONTEXT: Effective treatment of attention-deficit/hyperactivity disorder (ADHD) is essential to improving youth outcomes. OBJECTIVES: This systematic review provides an overview of the available treatment options. DATA SOURCES: We identified controlled treatment evaluations in 12 databases published from 1980 to June 2023; treatments were not restricted by intervention content. STUDY SELECTION: Studies in children and adolescents with clinically diagnosed ADHD, reporting patient health and psychosocial outcomes, were eligible. Publications were screened by trained reviewers, supported by machine learning. DATA EXTRACTION: Data were abstracted and critically appraised by 1 reviewer and checked by a methodologist. Data were pooled using random-effects models. Strength of evidence and applicability assessments followed Evidence-based Practice Center standards. RESULTS: In total, 312 studies reported in 540 publications were included. We grouped evidence for medication, psychosocial interventions, parent support, nutrition and supplements, neurofeedback, neurostimulation, physical exercise, complementary medicine, school interventions, and provider approaches. Several treatments improved ADHD symptoms. Medications had the strongest evidence base for improving outcomes, including disruptive behaviors and broadband measures, but were associated with adverse events. LIMITATIONS: We found limited evidence of studies comparing alternative treatments directly and indirect analyses identified few systematic differences across stimulants and nonstimulants. Identified combination of medication with youth-directed psychosocial interventions did not systematically produce better results than monotherapy, though few combinations have been evaluated. CONCLUSIONS: A growing number of treatments are available that improve ADHD symptoms and other outcomes, in particular for school-aged youth. Medication therapies remain important treatment options but are associated with adverse events.

Attention deficit and hyperactivity disorder and use of psychostimulants in Aotearoa, New Zealand: exploring the treatment gap.

Introduction Attention deficit and hyperactivity disorder (ADHD) is a common neurodevelopmental disorder affecting about 7% of those aged up to 12 years, 5% of teenagers and 3% of adults. It is associated with poor academic performance, substance abuse, criminality, poor social functioning and other negative outcomes. Psychotherapeutic treatment is moderately successful, whereas pharmacotherapy with stimulant medication is more efficacious and is recommended in many international guidelines. Anecdotal evidence suggests underuse of these medications in Aotearoa, New Zealand. Aim To estimate how many patients with ADHD are prescribed psychostimulants in Aotearoa, New Zealand. Methods National prescribing data for dexamphetamine and methylphenidate in 2022 were obtained and matched against estimated prevalence of ADHD by age. Results There is a significant treatment gap for which inability to access first-line medication is likely to be the predominant explanation. Discussion The data suggest failure of our health system to provide reasonable health care for a significant number of people with ADHD, and results in inequity in outcomes. New approaches are needed that will increase access to first-line medication, yet maintain appropriateness of diagnosis and limit risk of medication diversion.

Memory loss induced by lisdexamfetamine in the rat: A behavioral, electrophysiological, and histopathological Study.

Lisdexamfetamine (LDX) is one of the drugs commonly used to treat attention deficit hyperactivity disorder (ADHD). However, its neurological side effects, particularly on cognition, are not fully understood. The present study focused on memory in rats treated with four weeks of LDX injection. We compared LDX-treated rats with control ones, using several methods to evaluate the behavioral responses and electrophysiological, molecular, and histological properties in the hippocampus. Our findings demonstrated that subchronic administration of LDX impaired behavioral performance in all memory assessment tests (Y maze, Morris Water Maze, and Shuttle box). Although LDX did not alter population spike (PS) amplitude, it increased the field excitatory postsynaptic potential (fEPSP) slope of evoked potentials of LTP components. Also, in addition to an increase in expression of caspase-3 in the hippocampus, which indicates the susceptibility to apoptosis in LDX-treated rats, the number of microglia and astrocytes went up significantly in the LDX group. Moreover, Sholl's analysis showed an increase in the soma size and total process length in both hippocampal astrocytes and microglia. Overall, because of these destructive effects of LDX on the hippocampus, which is one of the critical memory-related areas of the brain, the findings of this investigation provide evidence to show the disruption of memory-related variables following the LDX. However, more research is needed to clarify it.

Attention-Deficit Hyperactivity Disorder (ADHD) Medication Use Trajectories Among Women in the Perinatal Period.

BACKGROUND: An increasing number of women of reproductive age are treated with attention-deficit hyperactivity disorder (ADHD) medication; however, patterns of ADHD medication use for women in the perinatal period have not been well described. OBJECTIVE: This study aimed to describe ADHD medication use patterns from 1 year before pregnancy to 1 year after delivery, and to describe sociodemographic characteristics and clinical features by medication trajectories. METHODS: The population-based cohort study included pregnancies in Denmark between 1997 and 2020, from the Medical Birth Register, by women who filled at least one prescription for ADHD medication from 12 months before pregnancy until 12 months after delivery. We applied group-based trajectory modeling to classify women into subgroups based on the identification of heterogeneous ADHD medication treatment patterns, and described the characteristics associated with these groups. RESULTS: Overall, we included 4717 pregnancies leading to liveborn singletons by 4052 mothers with a mean (standard deviation) age of 27.5 (5.6) years. We identified four treatment trajectories across pregnancy and the postpartum period: continuers (23.3%), discontinuers (41.8%), interrupters who ceased filling prescriptions during pregnancy but resumed postpartum (17.2%), and postpartum initiators (17.7%). Continuers were older at the time of conception, gave birth in more recent years, were more likely to smoke during pregnancy, and used other psychotropic medications during pregnancy. A large proportion of continuers used methylphenidate (89.1%) compared with the other groups (75.9-84.1%) and had switched ADHD medication type during the whole period (16.4% vs. 7.4-14.8%). CONCLUSION: We found that approximately 60% of women discontinued or interrupted their ADHD medication around pregnancy, and those who continued differed in sociodemographic and clinical factors that may reflect more severe ADHD.

A systematic review and meta-analysis of synthetic cathinone use and psychosis.

RATIONALE: Synthetic cathinones (SC), commonly referred to as "bath salts", are stimulants resembling the natural alkaloid cathinone found in the khat plant. These substances have the potential to induce serious health risks such as hallucinations, delusions, paranoia and agitation which can lead to substance-induced psychotic disorders. Despite growing concerns, there is a limited understanding of the association between SC consumption and the devolvement of such psychopathologies. METHODS: We conducted a systematic review to investigate the frequency of substance-induced psychotic disorder (SIPD) and associated conditions in humans following synthetic cathinone consumption. We qualitatively and quantitatively analyzed SC exposure cases. RESULTS: A total of 32 studies were included, with a diverse range of demographics, synthetic cathinone types, and consumption patterns. The proportion of individuals developing psychotic symptoms was reported at 0.380 (Random-effects model, 95% CI 0.289 - 0.475). Additionally, the significant heterogeneity in diagnostic approaches limited our ability to provide a precise estimate of prevalence. CONCLUSIONS: Synthetic cathinone consumption is associated with the risk of developing psychotic symptoms as indicated by the prevalence of hallucinations and/or delusions. Due to the lack of information on classifying factors, particularly duration of symptoms, we are unable to conclude synthetic cathinone-induced psychosis. Further research is warranted to elucidate the underlying mechanism linking synthetic cathinone consumption and psychosis. This review underscores the urgency of addressing the growing health risks posed by synthetic cathinone use. Additionally, it highlights the necessity of proper quantification of psychotic symptoms through scales and reporting of classification criteria to accurately diagnose SIPD.

Effects of acute and chronic methylphenidate on prepulse inhibition: A sex difference study in Wistar rats.

BACKGROUND: The utilization of methylphenidate (MPH) is experiencing a notable surge within the adult population. This growth can be attributed to two key factors: its recreational and cognitive enhancement purposes, as well as the rising prevalence of ADHD diagnoses within this population. This study examined acute and chronic oral MPH effects on attention in male and female Wistar rats. To this end, we used a prepulse inhibition (PPI) task, which is widely used to assess psychoactive drug effects in both humans and rodents. This task allowed us to evaluate changes in attention by analyzing sensorimotor gating associated with stimulus selection process. METHODS: Animals were administered a clinically relevant dose of MPH (5 mg/kg) daily for seven days. The estrous cycle phases of the female rats were measured during behavioral sessions. The PPI task was conducted 20 min after drug administration on day 1 (acute), day 7 (chronic), and 48 h post-treatment. RESULTS: Results indicated that both acute and chronic MPH treatment impaired PPI expression in male rats, but not in female rats, regardless of their estrous cycle phase. Furthermore, a differential effect of chronic MPH treatment on the PPI task was found in male rats. Specifically, on the seventh treatment day, the PPI effect was observed when animals undertook the PPI task for the first time but was impaired in those animals in which the initial PPI session occurred under the acute influence of the drug (day 1). CONCLUSIONS: These findings suggest that the impact of MPH on sensorimotor gating responses may vary based on sex and task experience, possibly leading to state-dependent effects in healthy individuals.

Involvement of nucleus accumbens SERCA2b in methamphetamine-induced conditioned place preference.

Methamphetamine (METH) is a highly addictive psycho-stimulant that induces addictive behaviour by stimulating increased dopamine release in the nucleus accumbens (NAc). The sarco/endoplasmic reticulum calcium ion transport ATPases (SERCA or ATP2A) is a calcium ion (Ca2+) pump in the endoplasmic reticulum (ER) membrane. SERCA2b is a SERCA subtype mainly distributed in the central nervous system. This study used conditioned place preference (CPP), a translational drug reward model, to observe the effects of SERCA and SERCA2b on METH-CPP in mice. Result suggested that the activity of SERCA was significantly decreased in NAc after METH-CPP. Intraperitoneal SERCA agonist CDN1163 injection or bilateral CDN1163 microinjection in the NAc inhibited METH-CPP formation. SERCA2b overexpression by the Adeno-associated virus can reduce the DA release of NAc and inhibit METH-CPP formation. Although microinjection of SERCA inhibitor thapsigargin in the bilateral NAc did not significantly aggravate METH-CPP, interference with SERCA2b expression in NAc by adeno-associated virus increased DA release and promoted METH-CPP formation. METH reduced the SERCA ability to transport Ca2+ into the ER in SHSY5Y cells in vitro, which was reversed by CDN1163. This study revealed that METH dysregulates intracellular calcium balance by downregulating SERCA2b function, increasing DA release in NAc and inducing METH-CPP formation. Drugs that target SERCA2b may have the potential to treat METH addiction.

Suicide, Stimulants, and Selective Serotonin Reuptake Inhibitors: A Retrospective Chart Review.

Background: Previous studies suggest that selective serotonin reuptake inhibitors (SSRIs) may increase the risk of suicide among children and youth, although the association between suicide risk and the combination of SSRIs with other medication such as stimulants in this population remains unclear. This study explored whether the combination of SSRIs with stimulants influenced suicide risk. Methods: A retrospective cohort study was conducted at a single children's hospital campus-based ambulatory psychiatric clinic between September 1, 2017, and September 30, 2020. Subjects were 6-21 years of age and prescribed either stimulants or stimulants and SSRIs only. The primary outcome was suicidal thoughts and behaviors (STB), defined by documented suicidal thoughts, plans, or behaviors. Firth logistic regression evaluated associations between medication class and STB. Results: Among 349 patients, the prevalence of STB was 5.7% (n = 20). In unadjusted model, patients prescribed SSRIs and stimulants had a 2.9-fold increase of STB compared to patients prescribed stimulants only, along with increasing age, male sex, and the diagnoses of anxiety and/or depression. In the final model adjusted for each of these factors, the observed association of medication regiment with STB was attenuated (odds ratio [OR]: 1.3, confidence interval [CI]: 0.3-4.9, p = 0.7). The magnitude of the adjusted association between depressive diagnosis and STB was notable (OR: 3.6, CI: 1.0-12.6, p = 0.049). Conclusions: Among patients followed in a children's hospital-based ambulatory psychiatric clinic, a combination medication regimen of SSRIs and stimulants after adjusting for genetic sex, age, anxiety diagnosis, and depression diagnosis, the observed association between STB and combination stimulant and SSRI treatment was attenuated. This finding suggests that other factors, including depression, may have contributed to the association between SSRI treatment and STB. Larger, prospective studies of the relationship between combination pharmacotherapy and suicide risk are warranted to guide clinical/pharmacological decision making and to better clarify these relationships.