Life-threatening interactions between HIV-1 protease inhibitors and the illicit drugs MDMA and gamma-hydroxybutyrate

Zinc Supplementation Reduces ROS Production and Prevents MDMA-Induced Apoptosis in TM3 Leydig Cells via the Inhibition of Pro-Apoptotic Proteins

MDMA can cause serious adverse effects on vital organs such as the heart, brain, and liver. Additionally, MDMA consumption can also potentially cause various endocrine system dysfunctions. The previous study has shown that pre-treatment of zinc can reduce the cytotoxicity of MDMA on the Leydig cell line (TM3). In this study, we investigated the mechanisms involved in the treatment with MDMA on the apoptosis of TM3 cells and the effects of zinc pre-treatment on reducing the apoptotic effects of MDMA. TM3 cells were incubated with MDMA (5 mM), zinc (8 µM), and zinc (8 µM) prior to MDMA (5 mM) for 48 h. The cells were pre-treated with zinc for 24 h prior to the administration of MDMA, and the total culture time was 48h. The effect of different treatment groups in causing oxidative stress and apoptosis in TM3 cells was measured by DCF, TUNNEL, and western blot tests, respectively. Our results revealed that the number of DCF and tunnel-positive cells increases as a result of MDMA treatment. In addition, the treatment with MDMA increased the expression of pro-apoptotic proteins caspase 3, Bax, and p53. Conversely, the expression of anti-apoptotic protein Bcl-2 decreased. Zinc pre-treatment significantly decreased the expression of pro-apoptotic proteins and the number of tunnels and DCF-positive cells compared to the MDMA-only group. It is concluded that MDMA has a toxic effect and causes apoptosis on TM3 cells, and also, pre-treatment with zinc mitigates the ROS production and toxic effect of MDMA and MDMA-induced apoptosis in TM3 cells.

Ecstasy, molly, MDMA: What health practitioners need to know about this common recreational drug

3,4-methylenedioxymethamphetamine (MDMA; commonly referred to as "ecstasy" or "molly") is a substituted amphetamine drug that is used recreationally for its acute psychoactive effects, including euphoria and increased energy, as well as prosocial effects such as increased empathy and feelings of closeness with others. Acute adverse effects can include hyperthermia, dehydration, bruxism, and diaphoresis. Post-intoxication phenomena may include insomnia, anhedonia, anxiety, depression, and memory impairment, which can persist for days following drug cessation. MDMA acts as a releasing agent for monoamine neurotransmitters, including dopamine (DA), norepinephrine (NE) and serotonin (5-HT), by interfering with vesicular storage and transporter function, thus increasing extracellular levels of DA, NE, and 5-HT. Medical intervention in response to adverse events is complicated by the fact that illicitly-acquired MDMA is frequently adulterated, contaminated, or outright replaced with other psychoactive drugs such as synthetic cathinones ("bath salts") or methamphetamine, often unknown to the person using the drug. This review provides background on the legal status of MDMA and its use patterns, including proposals for its use as an adjunct in psychotherapy. It also discusses the pharmacological properties, mental and physical health effects, and interactions of MDMA with other drugs, with special focus on harm reduction strategies. This information will help healthcare providers assess adverse health effects related to MDMA/ecstasy use in order to facilitate appropriate treatment strategies and improve patient outcomes.

Amphetamine-related intoxications in people living with HIV: An observational study in an emergency department in Barcelona (Spain) from 2018 to 2020

BACKGROUND

Stimulant drugs, particularly amphetamines, are more commonly implicated in drug-related deaths in people living with HIV; however, the clinical characteristics of amphetamine-related intoxication in people living with HIV are poorly described.

MATERIAL AND METHODS

We conducted a retrospective study in people living with HIV who were admitted for amphetamine-related intoxication to an emergency department of a teaching hospital between 2018 and 2021. Severe intoxication (SI) was arbitrarily defined as requiring admission to the emergency medical support unit and receiving medical treatment for ≥6 h.

RESULTS

In total, 170 male patients with a median age of 36.2 + 7.5 years were included in the study. A total of 77 (45.3%) individuals had mental disorders, and 120 (85.7%) had HIV-1 RNA suppression, with a median CD4 cell count of 696 (interquartile range 490-905). In total, 61 (37.9%) individuals were on ritonavir/cobicistat-based regimens. Presenting clinical syndromes included agitation in 60 (35.3%) subjects, anxiety in 37 (21.7%), psychosis in 27 (15.8%), chest pain in 26 (15.3%) and altered level of consciousness in 20 (11.7%). SI was observed in 48 (28.2%) individuals, 12 (7.1%) required admission to the intensive care unit, and two (1.2%) died. Altered level of consciousness (odds ratio [OR] 6.5; 95% confidence interval [CI] 2.2-18.9; p < 0.01), psychosis (OR 5.8; 95% CI 2.2-15.1; p < 0.01) and suicide attempt (OR 4.6; 95% CI 1.8-11.6; p 0.01) were associated with SI in the adjusted analysis.

CONCLUSIONS

Amphetamine-related intoxication causes high morbidity in people living with HIV. Healthcare providers serving these patients should consider incorporating harm-reduction measures in the prevention of amphetamine-related intoxication.

Do ART and Chemsex Drugs Get Along? Potential Drug-Drug Interactions in a Cohort of People Living with HIV Who Engaged in Chemsex: A Retrospective Observational Study

INTRODUCTION

People living with HIV (PLWH) who engaged in chemsex are at risk of potential drug-drug interactions (pDDIs) with recreational drugs. This study aimed to characterize pDDIs between antiretroviral treatment (ART) and chemsex drugs and evaluate their association with unscheduled relevant hospital consultations.

METHODS

We conducted a single-center, retrospective, observational study in a series of gay, bisexual, and other men who have sex with men (gbMSM) living with HIV who engaged in chemsex and who attended a tertiary hospital in Barcelona, Spain, from February 2018 through August 2019. Associations between all recorded pDDIs and relevant unscheduled consultations were estimated using the incidence rate (IR) per 100 person-years of those events compared between patients with no pDDI (green flag) or moderate severity pDDI (orange flag) with patients with high severity pDDI (red flag) using the incidence rate ratio (IRR).

RESULTS

Among 172 PLWH engaged in chemsex, 249 ART regimens were prescribed: 44% based on integrase inhibitors, 30% on boosted ART, and 26% based on non-nucleoside reverse transcriptase inhibitors. The substances and recreational drugs most frequently used were erectile dysfunction agents (83%), methamphetamine (79%), GHB (77%), and alkyl nitrites (71%). Polydrug use was reported in 52%. We observed 2048 pDDIs. Of these, 23% were orange flag pDDIs; 88% related to boosted ARTs. The IR of the 285 unscheduled relevant episodes in patients with orange flag pDDIs was 64.67 (95% CI 40.07-89.28). The IRR of green flag pDDIs was 1.05 (95% CI 0.60-1.8; p = 0.876).

CONCLUSION

One in four pDDIs were of moderate severity but no significant increase in the incidence of unscheduled relevant consultations was observed. A high number of unscheduled consultations, predominantly for psychiatric events and intoxication, were observed. Beyond using non-boosted ART to minimize pDDIs, other factors related to the practice of chemsex must be addressed, in order to offer a better approach.

HIV, chemsex, and the need for harm-reduction interventions to support gay, bisexual, and other men who have sex with men

Numerous studies have identified an association between the use of drugs in sexual contexts (chemsex) and HIV among gay, bisexual, and other men who have sex with men (GBMSM), although whether a causal relationship exists is contentious. An intricate relationship exists between chemsex, HIV treatment and prevention, harm reduction, and the provision of community-grounded health services. Furthermore, potential harms exist beyond HIV, such as intoxication and overdose. Community-engaged responses to chemsex involve social and cultural strategies of harm reduction and sexual health promotion before, during, and after a chemsex session. Ultimately, this Review calls for actions and collaborations aimed at developing a greater understanding of chemsex as a practice within different GBMSM subpopulations and to develop tailored harm-reduction models that can accommodate GBMSM who engage in chemsex in various ways and with varied effects.

Increasing emergency department admissions for chemsex-related intoxications in Barcelona, Spain, among people living with HIV: an observational study from 2018 to 2020

Background

Chemsex is a novel phenomenon referring to the use of drugs, including crystal methamphetamine, gammahydroxybutyric acid (GHB)/gamma-butyrolactone (GABA) and mephedrone, to facilitate, enhance, and prolong the sexual experience in men who have sex with men in large cities internationally. There is a growing concern about chemsex and fatal cases among people living with HIV on antiretroviral therapy. This study aimed to describe the clinical characteristics of chemsex-related intoxications.

Material and methods

An observational study was conducted in people living with HIV who were admitted for chemsex-related intoxications in an emergency department of a teaching hospital in Barcelona, Spain, from 2018 to 2020. Severe acute intoxications were defined according to the Poisoning Severity Score.

Results

One hundred and fifteen male patients with a median age of 35.6±7 years were included in the study:15 (13.1%) in 2018, 32 (27.8%) in 2019 and 68 (59.1%) in 2020. All patients had stable housing, 107(93.0%) were Spanish citizen and 32 (27.8%) had mental health disorders. Median CD4 lymphocyte count was 624 (500–765) cells/mm³ and 99 (86.1%) had HIV-1 RNA suppression.

Poly-drug use was observed in 51(44.3%) cases and methamphetamine in 75(65,2%) and gammahydroxibutiric acid in 68 (59.1%) were the main drugs used.

Potential drug interactions due to the inhibition of cytochrome P450 by antiviral therapy was determined in 36 (31.3%) patients. Severe intoxications cases affecting neurologic and respiratory systems were diagnosed in 12 (10.4%) patients and no patient died. CD4 cell counts ≤500 cells (O.R.:4.2; C.I.95%:1.2–14.6) and mental health disorders (O.R.: 2.9; C. I 95%: 0.8–9.9) were associated with severe acute drug intoxications in the bivariate analyses.

Conclusions

Chemsex-related intoxications are an increasing clinical problem in people living with HIV. Chemsex should be routinely screened and addressed in clinical practice, particularly for people with mental illness and low CD4 cell counts, who are at higher risk for severe intoxications.

Chemsex and antiretroviral prescribing in an HIV cohort in Brighton, UK

OBJECTIVES

Chemsex has been reported among men who have sex with men (MSM) living with HIV. There have been concerns about potentially harmful drug-drug interactions between chemsex drugs and antiretroviral therapy (ritonavir and cobicistat). We aimed to describe the prevalence and patterns of chemsex users in our HIV clinic population and to evaluate antiretroviral prescribing among chemsex users.

METHODS

We undertook a cross-sectional study of patients attending our HIV clinic between January 2019 and December 2020. We collected data on patients who disclosed recent recreational drug use including chemsex in the previous 3 months.

RESULTS

In all, 2202/2501 (88%) patients were asked about recreational drug use and 514 (23%) disclosed recreational drug use. Eighty-two (4%) of these disclosed recent chemsex; 73 (89%) used crystal methamphetamine, 51 (62%) used gamma-hydroxybutyrate (GHB)/gamma-butyrolactone (GBL), 55 (67%) reported poly-drug use and 63 (76%) reported injecting drug use. The chemsex users were all cis-male MSM and were significantly older (53 vs. 46 years, p < 0.0001), and more likely to have had previous syphilis (73% vs. 28%, p < 0.0001) than patients reporting non-chemsex drug use. All chemsex users were prescribed antiretrovirals and 74 (90%) had an undetectable HIV viral load; 31 (38%) patients were taking either ritonavir (N = 12) or cobicistat (N = 19) as part of their antiretroviral regimen and this was similar to other patients attending for HIV care [31/82 (38%) vs. 768/2419 (31%), p = 0.25].

CONCLUSIONS

The prevalence of chemsex users among our HIV clinic attendants is 4%, and 38% of these were prescribed either ritonavir or cobicistat. Chemsex use should be a factor in antiretroviral therapy decision-making to avoid potential harm.

Absence of drug-drug interactions between γ-hydroxybutyric acid (GHB) and cobicistat

OBJECTIVES

Potential interactions between CYP3A4 inhibitors and γ-hydroxybutyric acid (GHB) have been suggested as a possible explanation for cases of GHB overdose in recent years among people living with HIV engaged in chemsex. Our objective was to assess the effect of cobicistat on the pharmacokinetics of GHB.

METHODS

Fifteen healthy adults were enrolled in this randomized, double-blind, placebo-controlled, two-arm, crossover clinical trial. Participants underwent two 5 day treatment periods with at least a 1 week washout period between them. In each treatment period, participants received cobicistat (150 mg q24h orally) or matched placebo. On day 5 of each treatment period, participants were given a single oral dose of GHB (25 mg/kg). Plasma concentrations of GHB, subjective effects, blood pressure, heart rate and oxygen saturation were monitored for 5 h after dosing. GHB pharmacokinetic and pharmacodynamic parameters were calculated for each participant during each study period by non-compartmental analysis and were compared using linear mixed-effects models. The study was registered at https://www.clinicaltrialsregister.eu (Eudra-CT number 2019-002122-71) and at https://clinicaltrials.gov (NCT04322214).

RESULTS

Ten participants completed the two study periods. No drug-related adverse events that necessitated subject withdrawal or medical intervention occurred during the study. Compared with placebo, none of the primary pharmacokinetic parameters of GHB was substantially changed by the administration of GHB with cobicistat. Similarly, no differences regarding subjective or physiological effects were observed when GHB was administered alone or with cobicistat.

CONCLUSIONS

Neither pharmacokinetic nor pharmacodynamic drug-drug interactions between cobicistat and GHB were identified in this study.

Novel Phenethylamines and Their Potential Interactions With Prescription Drugs: A Systematic Critical Review

BACKGROUND

The novel phenethylamines 4-fluoroamphetamine (4-FA) and 2,5-dimethoxy-4-bromophenethylamine (2C-B) fall in the top 10 most used new psychoactive substances (NPSs) among high-risk substance users. Various phenethylamines and NPS are also highly used in populations with mental disorders, depression, or attention deficit hyperactivity disorder (ADHD). Moreover, NPS use is highly prevalent among men and women with risky sexual behavior. Considering these specific populations and their frequent concurrent use of drugs, such as antidepressants, ADHD medication, and antiretrovirals, reports on potential interactions between these drugs, and phenethylamines 4-FA and 2C-B, were reviewed.

METHODS

The authors performed a systematic literature review on 4-FA and 2C-B interactions with antidepressants (citalopram, fluoxetine, fluvoxamine, paroxetine, sertraline, duloxetine, bupropion, venlafaxine, phenelzine, moclobemide, and tranylcypromine), ADHD medications (atomoxetine, dexamphetamine, methylphenidate, and modafinil), and antiretrovirals.

RESULTS

Limited literature exists on the pharmacokinetics and drug-drug interactions of 2C-B and 4-FA. Only one case report indicated a possible interaction between 4-FA and ADHD medication. Although pharmacokinetic interactions between 4-FA and prescription drugs remain speculative, their pharmacodynamic points toward interactions between 4-FA and ADHD medication and antidepressants. The pharmacokinetic and pharmacodynamic profile of 2C-B also points toward such interactions, between 2C-B and prescription drugs such as antidepressants and ADHD medication.

CONCLUSIONS

A drug-drug (phenethylamine-prescription drug) interaction potential is anticipated, mainly involving monoamine oxidases for 2C-B and 4-FA, with monoamine transporters being more specific to 4-FA.

In-Silico Modeling in Drug Metabolism and Interaction: Current Strategies of Lead Discovery

BACKGROUND

Drug metabolism is a complex mechanism of human body systems to detoxify foreign particles, chemicals, and drugs through bio alterations. It involves many biochemical reactions carried out by invivo enzyme systems present in the liver, kidney, intestine, lungs, and plasma. After drug administration, it crosses several biological membranes to reach into the target site for binding and produces the therapeutic response. After that, it may undergo detoxification and excretion to get rid of the biological systems. Most of the drugs and its metabolites are excreted through kidney via urination. Some drugs and their metabolites enter into intestinal mucosa and excrete through feces. Few of the drugs enter into hepatic circulation where they go into the intestinal tract. The drug leaves the liver via the bile duct and is excreted through feces. Therefore, the study of total methodology of drug biotransformation and interactions with various targets is costly.

METHODS

To minimize time and cost, in-silico algorithms have been utilized for lead-like drug discovery. Insilico modeling is the process where a computer model with a suitable algorithm is developed to perform a controlled experiment. It involves the combination of both in-vivo and in-vitro experimentation with virtual trials, eliminating the non-significant variables from a large number of variable parameters. Whereas, the major challenge for the experimenter is the selection and validation of the preferred model, as well as precise simulation in real physiological status.

RESULTS

The present review discussed the application of in-silico models to predict absorption, distribution, metabolism, and excretion (ADME) properties of drug molecules and also access the net rate of metabolism of a compound.

CONCLUSION

It helps with the identification of enzyme isoforms; which are likely to metabolize a compound, as well as the concentration dependence of metabolism and the identification of expected metabolites. In terms of drug-drug interactions (DDIs), models have been described for the inhibition of metabolism of one compound by another, and for the compound-dependent induction of drug-metabolizing enzymes.

Factors Associated with Drug Use Among HIV-Infected Men Who Have Sex with Men in China

Drug use is globally more prevalent in HIV-positive men who have sex with men (HIVMSM) than their heterosexual counterparts. Yet, few studies have investigated the factors associated with drug use among this population beyond Western societies. A cross-sectional survey was conducted to examine factors associated with drug use among 415 HIVMSM in Chengdu, China. The results show that 10.8% of the participants had used drugs in the past 30 days. Among participants who had anal intercourse in the past 30 days, 11.5% had used drugs during anal intercourse. After adjusting for background variables, logistic regression models show that life satisfaction was associated with past 30-day drug use [Adjusted Odds Ratio (ORa) = 0.90, p < 0.001], and with drug use during anal intercourse in the past 30 days (ORa = 0.89, p < 0.01). Participants with more nonregular partners were more likely to use drugs with or without sex in the past 30 days, whereas those with one regular partner were less likely to use drugs during anal intercourse compared to their counterparts with no regular partners. The findings of this study are informative for designing effective substance-use intervention programs targeting HIVMSM.

The Moderating Role of Social Support on the Relationship Between Anxiety, Stigma, and Intention to Use Illicit Drugs Among HIV-Positive Men Who Have Sex with Men

The present study examined the association between anxiety, stigma, social support and intention to use illicit drugs, and the moderating role of social support on the association between anxiety/stigma and intention to use illicit drugs among 450 Chinese HIV-positive MSM. Findings show that controlling for significant background variables, self-stigma and anxiety were positively associated with intention to use illicit drugs, while social support was negatively associated with intention to use illicit drugs. A significant moderation effect of social support was also observed, that the negative association between self-stigma/anxiety and intention to use illicit drugs was only significant among participants with lower levels of social support. Findings highlight the importance of reducing self-stigma and anxiety, and promoting social support in drug use prevention for HIV-positive MSM.

Numerical Analysis of Time-Dependent Inhibition by MDMA

Methylenedioxymethamphetamine (MDMA) is a known drug of abuse and schedule 1 narcotic under the Controlled Substances Act. Previous pharmacokinetic work on MDMA used classic linearization techniques to conclude irreversible mechanism-based inhibition of CYP2D6. The current work challenges this outcome by assessing the possibility of two alternative reversible kinetic inhibition mechanisms known as the quasi-irreversible (QI) model and equilibrium model (EM). In addition, progress curve experiments were used to investigate the residual metabolism of MDMA by liver microsomes and CYP2D6 baculosomes over incubation periods up to 30 minutes. These experiments revealed activity in a terminal linear phase at the fractional rates with respect to initial turnover of 0.0354 ± 0.0089 in human liver microsomes and 0.0114 ± 0.0025 in baculosomes. Numerical model fits to percentage of remaining activity (PRA) data were consistent with progress curve modeling results, wherein an irreversible inhibition pathway was found unnecessary for good fit scoring. Both QI and EM kinetic mechanisms fit the PRA data well, although in CYP2D6 baculosomes the inclusion of an irreversible inactivation pathway did not allow for convergence to a reasonable fit. The kinetic complexity accessible to numerical modeling has been used to determine that MDMA is not an irreversible inactivator of CYP2D6, and instead follows what can be generally referred to as slowly reversible inhibition. SIGNIFICANCE STATEMENT: The work herein describes the usage of computational models to delineate between irreversible and slowly reversible time-dependent inhibition. Such models are used in the paper to analyze MDMA and classify it as a reversible time-dependent inhibitor.

Adverse pharmacokinetic interactions between illicit substances and clinical drugs

Adverse pharmacokinetic interactions between illicit substances and clinical drugs are of a significant health concern. Illicit substances are taken by healthy individuals as well as by patients with medical conditions such as mental illnesses, acquired immunodeficiency syndrome, diabetes mellitus and cancer. Many individuals that use illicit substances simultaneously take clinical drugs meant for targeted treatment. This concomitant usage can lead to life-threatening pharmacokinetic interactions between illicit substances and clinical drugs. Optimal levels and activity of drug-metabolizing enzymes and drug-transporters are crucial for metabolism and disposition of illicit substances as well as clinical drugs. However, both illicit substances and clinical drugs can induce changes in the expression and/or activity of drug-metabolizing enzymes and drug-transporters. Consequently, with concomitant usage, illicit substances can adversely influence the therapeutic outcome of coadministered clinical drugs. Likewise, clinical drugs can adversely affect the response of coadministered illicit substances. While the interactions between illicit substances and clinical drugs pose a tremendous health and financial burden, they lack a similar level of attention as drug-drug, food-drug, supplement-drug, herb-drug, disease-drug, or other substance-drug interactions such as alcohol-drug and tobacco-drug interactions. This review highlights the clinical pharmacokinetic interactions between clinical drugs and commonly used illicit substances such as cannabis, cocaine and 3, 4-Methylenedioxymethamphetamine (MDMA). Rigorous efforts are warranted to further understand the underlying mechanisms responsible for these clinical pharmacokinetic interactions. It is also critical to extend the awareness of the life-threatening adverse interactions to both health care professionals and patients.

Pharmacological Treatment in γ-Hydroxybutyrate (GHB) and γ-Butyrolactone (GBL) Dependence: Detoxification and Relapse Prevention

The misuse of γ-hydroxybutyrate (GHB) for recreational purposes has resulted in an increase in GHB-related problems such as intoxications, dependence and withdrawal in several countries in Europe, Australia and the US over the last decade. However, prevalence rates of misuse of GHB and its precursor, γ-butyrolactone (GBL), are still relatively low. In this qualitative review paper, after a short introduction on the pharmacology of GHB/GBL, followed by a summary of the epidemiology of GHB abuse, an overview of GHB dependence syndrome and GHB/GBL withdrawal syndrome is provided. Finally, the existing literature on management of GHB detoxification, both planned and unplanned, as well as the available management of GHB withdrawal syndrome, is summarized. Although no systematic studies on detoxification and management of withdrawal have been performed to date, general recommendations are given on pharmacological treatment and preferred treatment setting.

MDMA-assisted therapy: A new treatment model for social anxiety in autistic adults

The first study of 3,4-methylenedioxymethamphetamine (MDMA)-assisted therapy for the treatment of social anxiety in autistic adults commenced in the spring of 2014. The search for psychotherapeutic options for autistic individuals is imperative considering the lack of effective conventional treatments for mental health diagnoses that are common in this population. Serious Adverse Events (SAEs) involving the administration of MDMA in clinical trials have been rare and non-life threatening. To date, MDMA has been administered to over 1133 individuals for research purposes without the occurrence of unexpected drug-related SAEs that require expedited reporting per FDA regulations. Now that safety parameters for limited use of MDMA in clinical settings have been established, a case can be made to further develop MDMA-assisted therapeutic interventions that could support autistic adults in increasing social adaptability among the typically developing population. As in the case with classic hallucinogens and other psychedelic drugs, MDMA catalyzes shifts toward openness and introspection that do not require ongoing administration to achieve lasting benefits. This infrequent dosing mitigates adverse event frequency and improves the risk/benefit ratio of MDMA, which may provide a significant advantage over medications that require daily dosing. Consequently, clinicians could employ new treatment models for social anxiety or similar types of distress administering MDMA on one to several occasions within the context of a supportive and integrative psychotherapy protocol.

Stakeholders' Views on Barriers to Research on Controversial Controlled Substances

Many diseases and disease symptoms still lack effective treatment. At the same time, certain controversial Schedule I drugs, such as heroin and cannabis, have been reputed to have considerable therapeutic potential for addressing significant medical problems. Yet, there is a paucity of U.S. clinical studies on the therapeutic uses of controlled drugs. For example, people living with HIV/AIDS experience a variety of disease- and medication-related symptoms. Their chronic pain is intense, frequent, and difficult to treat. Nevertheless, clinical trials of compassionate management for their chronic symptoms, which should be a research priority, are stymied. We employed qualitative methods to develop an understanding of the barriers to research on potential therapeutic uses of Schedule I drugs so that they might be addressed. We elicited the perspectives of key stakeholder groups that would be involved in such studies: people living with HIV/AIDS, clinicians, and members of institutional review boards. As we identified obstacles to research, we found that all of the stakeholder groups arrived at the same conclusion, that clinical research on the therapeutic potential of these drugs is ethically required.

An Ethical Exploration of Barriers to Research on Controlled Drugs

We examine the ethical, social, and regulatory barriers that may hinder research on therapeutic potential of certain controversial controlled substances like marijuana, heroin, or ketamine. Hazards for individuals and society and potential adverse effects on communities may be good reasons for limiting access and justify careful monitoring of these substances. Overly strict regulations, fear of legal consequences, stigma associated with abuse and populations using illicit drugs, and lack of funding may, however, limit research on their considerable therapeutic potential. We review the surprisingly sparse literature and address the particular ethical concerns pertinent to research with illicit and addictive substances, such as undue inducement, informed consent, therapeutic misconception, and risk to participants, researchers, and institutions. We consider the perspectives of key research stakeholders and explore whether they may be infected with bias. We conclude by proposing an empirical research agenda to provide an evidentiary basis for ethical reasoning.

A Review of the Toxicity of HIV Medications II: Interactions with Drugs and Complementary and Alternative Medicine Products

For many patients today, HIV has become a chronic disease. For those patients who have access to and adhere to lifelong antiretroviral (ARV) therapy, the potential for drug-drug interactions has become a real and life-threatening concern. It is known that most ARV drug interactions occur through the cytochrome P450 (CYP) pathway. Medications for comorbid medical conditions, holistic supplements, and illicit drugs can be affected by CYP inhibitors and inducers and have the potential to cause harm and toxicity. Protease inhibitors (PIs) tend to inhibit CYP3A4, while most non-nucleoside reverse transcriptase inhibitors (NNRTIs) tend to induce the enzyme. As such, failure to adjust the dose of co-administered medications, such as statins and steroids, may lead to serious complications including rhabdomyolysis and hypercortisolism, respectively. Similarly, gastric acid blockers can decrease several ARV absorption, and warfarin doses may need to be adjusted to maintain therapeutic concentrations. Illicit drugs such as methylenedioxymethamphetamine (MDMA, "ecstasy") in combination with PIs lead to increased toxicity, while the concomitant administration of sedative drugs such as midazolam and alprazolam in patients taking PIs can result in prolonged sedation, delayed recovery, and increased length of stay. Even supplements like St. John's Wort can alter PI concentrations. In theory, any drug that is metabolized by CYP has potential for a pharmacokinetic drug-drug interaction with all PIs, cobicistat, and most NNRTIs. When adding a new medication to an ARV regimen, use of a drug-drug interaction software and/or consultation with a clinical pharmacist/pharmacologist or HIV specialist is recommended.

Pharmacokinetic drug interactions between drugs of abuse and antiretroviral medications: implications and management for clinical practice

Substance abuse and HIV/AIDS are two of the most serious, yet treatable diseases worldwide. Global access to HIV treatment continues to expand. In settings where both active illicit drug use and HIV treatment are concurrent, potentional problematic pharmacokinetic drug interactions may arise and complicate therapy. Clinical case series and carefully controlled pharmacokinetic interaction studies have been conducted between only a few drugs of abuse and approved antiretroviral therapies. Important pharmacokinetic drug interactions have been described for benzodiazepines, 3,4-methylenedioxymethamphetamine, methadone and buprenorphine; however, most have not been studied and few well-controlled studies have been conducted to adequately address the clinical implications of these interactions. The metabolism of drugs of abuse, description of the known interactions, and clinical implications and management of these interactions are reviewed. Certain interactions between drugs of abuse and antiretroviral therapies are known and others are likely based upon shared metabolic pathways. These may result in important clinical consequences. To optimize care, clinicians must be alert, knowledgeable about known and possible interactions and equipped to clinically manage the medical consequences. Moreover, there is considerable need for carefully controlled studies in this important and emerging area.

Antiretroviral medication: an emerging category of prescription drug misuse

BACKGROUND AND OBJECTIVES

Prescription drug abuse has been a focus of public health concern over the past two decades with many studies addressing patterns of narcotic analgesic abuse and diversion. Most research in this domain has centered on controlled substances with known abuse liability. However, the scientific literature has been virtually silent regarding other prescribed medications with previously undocumented addictive potential, such as antiretroviral (ARV) medications for treatment of human immunodeficiency virus.

METHODS

This article reviews the available evidence that suggests a growing problem of ARV diversion and abuse and explores the reasons for the misuse of these medications based on the theoretical neuropsychiatric effects of ARVs and the drug-drug interactions between ARVs and other drugs of abuse.

RESULTS

Review of media reports and qualitative studies suggest that ARV medications are emerging drugs of abuse. Claims about the psychoactive effects of ARV medications are supported by scientific case reports.

CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE

This article reviews the evidence to date of an emerging problem of diversion and misuse of ARV medications for recreational purposes. Implications of ARV misuse and diversion are discussed with suggestions for future research and intervention.

Toxicity of amphetamines: an update

Amphetamines represent a class of psychotropic compounds, widely abused for their stimulant, euphoric, anorectic, and, in some cases, emphathogenic, entactogenic, and hallucinogenic properties. These compounds derive from the β-phenylethylamine core structure and are kinetically and dynamically characterized by easily crossing the blood-brain barrier, to resist brain biotransformation and to release monoamine neurotransmitters from nerve endings. Although amphetamines are widely acknowledged as synthetic drugs, of which amphetamine, methamphetamine, and 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) are well-known examples, humans have used natural amphetamines for several millenniums, through the consumption of amphetamines produced in plants, namely cathinone (khat), obtained from the plant Catha edulis and ephedrine, obtained from various plants in the genus Ephedra. More recently, a wave of new amphetamines has emerged in the market, mainly constituted of cathinone derivatives, including mephedrone, methylone, methedrone, and buthylone, among others. Although intoxications by amphetamines continue to be common causes of emergency department and hospital admissions, it is frequent to find the sophism that amphetamine derivatives, namely those appearing more recently, are relatively safe. However, human intoxications by these drugs are increasingly being reported, with similar patterns compared to those previously seen with classical amphetamines. That is not surprising, considering the similar structures and mechanisms of action among the different amphetamines, conferring similar toxicokinetic and toxicological profiles to these compounds. The aim of the present review is to give an insight into the pharmacokinetics, general mechanisms of biological and toxicological actions, and the main target organs for the toxicity of amphetamines. Although there is still scarce knowledge from novel amphetamines to draw mechanistic insights, the long-studied classical amphetamines-amphetamine itself, as well as methamphetamine and MDMA, provide plenty of data that may be useful to predict toxicological outcome to improvident abusers and are for that reason the main focus of this review.

Non-injection drug use and HIV disease progression in the era of combination antiretroviral therapy

Little is known about the effects of non-injection drug use (NIDU) on HIV antiretroviral treatment outcomes. We conducted a systematic literature search and identified nine publications from prospective cohort studies investigating the relationship between NIDU and clinical HIV disease progression. Hazard ratios from studies estimating the effect of drug use on time to AIDS-related mortality ranged from 0.89 to 3.61, and only two of these were statistically significant. Hazard ratios from studies assessing time to an AIDS-defining event ranged from 1.19 to 2.51, with 8 of the 14 estimates falling between 1.55 and 1.65 regardless of drug use definition and measurement of use or frequency. It is suggested that NIDU may have a moderate effect of increasing the risk of progression to AIDS, but its impact on AIDS-related mortality is uncertain. NIDU may affect HIV antiretroviral treatment outcomes primarily through interaction with antiretroviral therapy and, to a lesser extent, through immune modulation and deterioration of general health. The limitations about published studies are discussed, and future perspectives on research on this topic are provided.

Efflux transporters- and cytochrome P-450-mediated interactions between drugs of abuse and antiretrovirals

Multidrug regimens and corresponding drug interactions cause many adverse reactions and treatment failures. Drug efflux transporters: P-gp, MRP, BCRP in conjunction with metabolizing enzymes (CYPs) are major factors in such interactions. Most effective combination antiretrovirals (ARV) therapy includes a PI or a NNRTI or two NRTI. Coadministration of such ARV may induce efflux transporters and/or CYP3A4 resulting in sub-therapeutic blood levels and therapeutic failure due to reduced absorption and/or increased metabolism. A similar prognosis is true for ARV-compounds and drugs of abuse combinations. Morphine and nicotine enhance CYP3A4 and MDR1 expression in vitro. A 2.5 fold rise of cortisol metabolite was evident in smokers relative to nonsmokers. Altered functions of efflux transporters and CYPs in response to ARV and drugs of abuse may result in altered drug absorption and metabolism. Appropriate in vitro models can be employed to predict such interactions. Influence of genetic polymorphism, SNP and inter-individual variation in drug response has been discussed. Complexity underlying the relationship between efflux transporters and CYP makes it difficult to predict the outcome of HAART as such, particularly when HIV patients taking drugs of abuse do not adhere to HAART regimens. HIV(+) pregnant women on HAART medications, indulging in drugs of abuse, may develop higher viral load due to such interactions and lead to increase in mother to child transmission of HIV. A multidisciplinary approach with clear understanding of mechanism of interactions may allow proper selection of regimens so that desired therapeutic outcome of HAART can be reached without any side effects.

Methadone, buprenorphine, and street drug interactions with antiretroviral medications

While street drugs appear unlikely to alter the metabolism of antiretroviral (ARV) medications, several ARVs may induce or inhibit metabolism of various street drugs. However, research on these interactions is limited. Case reports have documented life-threatening overdoses of ecstasy and gamma-hydroxybutyrate after starting ritonavir, an ARV that inhibits several metabolic enzymes. For opioid addiction, methadone or buprenorphine are the treatments of choice. Because a number of ARVs decrease or increase methadone levels, patients should be monitored for methadone withdrawal or toxicity when they start or stop ARVs. Most ARVs do not cause buprenorphine withdrawal or toxicity, even if they alter buprenorphine levels, with rare exceptions to date including atazanavir/ritonavir associated with significant increases in buprenorphine and adverse events related to sedation and mental status changes in some cases. There are newer medications yet to be studied with methadone or buprenorphine. Further, there are many frequently used medications in treatment of complications of HIV disease that have not been studied. There is need for continuing research to define these drug interactions and their clinical significance.

Mechanisms of MDMA (ecstasy)-induced oxidative stress, mitochondrial dysfunction, and organ damage

Despite numerous reports about the acute and sub-chronic toxicities caused by MDMA (3,4-methylenedioxymethamphetamine, ecstasy), the underlying mechanism of organ damage is poorly understood. The aim of this review is to present an update of the mechanistic studies on MDMA-mediated organ damage partly caused by increased oxidative/nitrosative stress. Because of the extensive reviews on MDMA-mediated oxidative stress and tissue damage, we specifically focus on the mechanisms and consequences of oxidative-modifications of mitochondrial proteins, leading to mitochondrial dysfunction. We briefly describe a method to systematically identify oxidatively-modified mitochondrial proteins in control and MDMA-exposed rats by using biotin-N-maleimide (biotin-NM) as a sensitive probe for oxidized proteins. We also describe various applications and advantages of this Cys-targeted proteomics method and alternative approaches to overcome potential limitations of this method in studying oxidized proteins from MDMA-exposed tissues. Finally we discuss the mechanism of synergistic drug-interaction between MDMA and other abused substances including alcohol (ethanol) as well as application of this redox-based proteomics method in translational studies for developing effective preventive and therapeutic agents against MDMA-induced organ damage.

Mechanism of 3,4-methylenedioxymethamphetamine (MDMA, ecstasy)-mediated mitochondrial dysfunction in rat liver

Despite numerous reports citing the acute hepatotoxicity caused by 3,4-methylenedioxymethamphetamine (MDMA) (ecstasy), the underlying mechanism of organ damage is poorly understood. We hypothesized that key mitochondrial proteins are oxidatively modified and inactivated in MDMA-exposed tissues. The aim of this study was to identify and investigate the mechanism of inactivation of oxidatively modified mitochondrial proteins, prior to the extensive mitochondrial dysfunction and liver damage following MDMA exposure. MDMA-treated rats showed abnormal liver histology with significant elevation in plasma transaminases, nitric oxide synthase, and the level of hydrogen peroxide. Oxidatively modified mitochondrial proteins in control and MDMA-exposed rats were labeled with biotin-N-maleimide (biotin-NM) as a sensitive probe for oxidized proteins, purified with streptavidin-agarose, and resolved using 2-DE. Comparative 2-DE analysis of biotin-NM-labeled proteins revealed markedly increased levels of oxidatively modified proteins following MDMA exposure. Mass spectrometric analysis identified oxidatively modified mitochondrial proteins involved in energy supply, fat metabolism, antioxidant defense, and chaperone activities. Among these, the activities of mitochondrial aldehyde dehydrogenase, 3-ketoacyl-CoA thiolases, and ATP synthase were significantly inhibited following MDMA exposure. Our data show for the first time that MDMA causes the oxidative inactivation of key mitochondrial enzymes which most likely contributes to mitochondrial dysfunction and subsequent liver damage in MDMA-exposed animals.

Analysis of HIV medication adherence in relation to person and treatment characteristics using hierarchical linear modeling

The purpose of this investigation was to consider person characteristics, treatment level variables, and illicit drug use to help explain the HIV antiviral adherence patterns of a community-based, non-drug-treatment-seeking sample of men who have sex with men (MSM). Adherence data were gathered for 300 MSM eight times over the course of 1 year using electronic monitoring. Treatment and person level characteristics were assessed at baseline assessment using computer-administered surveys, and drug usage was established via a diagnostic inventory. These longitudinal data were analyzed via Hierarchical Linear Modeling. The sample was diverse in terms of age and race/ethnicity. Across the span of the year in which the participants were assessed, adherence rates were relatively stable and high (means: 82% to 90%) at each time point and remained relatively stable across the yearlong investigation. Lower adherence rates were evident among those who were drug users, black identified (in terms of race), older, and by pill burden. Individuals on HIV antiretroviral therapy demonstrated consistent although not optimal adherence rates when assessed during the course of a year. The significance of numerous person level factors such as age, race, and drug use suggest that adherence to treatment may in part be impacted by the circumstances that the individual brings to the treatment behavior, and suggests interventions that delve beyond the behavioral to consider and address life social and intrapersonal circumstances that may interfere with adherence behaviors.

Drug interactions involving ethanol and alcoholic beverages

Ethanol is likely among the most widely and extensively used drugs in the world. It has also been demonstrated to alter the expression or activity of some drug-metabolizing enzymes. Thus, marked ethanol-provoked drug interactions could be of notable clinical importance. To date, relatively few clinically important interactions have been reported, involving cocaine, disulfiram and tacrolimus. Limited or modest interactions with ethanol have also been reported for drugs such as abacavir, cisapride, 'ecstasy' (3,4-methylenedioxymetamfetamine), gamma-hydroxybutyrate, methylyphenidate, metronidazole and verapamil. Most of these interactions do not seem to involve CYP2E1, the enzyme initially characterized and cloned based on its ability to metabolize and be induced by ethanol. Important work has elucidated the relationship between CYP2E1-mediated formation of the hepatotoxic metabolite of acetaminophen and alcohol consumption. Lastly, drug interactions involving other components of alcoholic beverages such as flavonoid and other polyphenolic components of red wine have been reported.

Apparent active transport of MDMA is not mediated by P-glycoprotein: a comparison with MDCK and Caco-2 monolayers

Amphetamines and their methylenedioxy derivatives generically display similar behavioral, physiologic and toxic effects. Inconsistent pharmacokinetic and toxicity data for methylenedioxymethamphetamine (MDMA) may suggest that active drug transporters are interacting with these compounds, and thus altering drug absorption and tissue distribution. In vitro models of CNS accumulation and intestinal drug transport were used to assess efflux transport of MDMA. Madin-Darby kidney cell epithelial (MDCK) monolayers displayed a 4-fold increase in accumulation in the basolateral to apical orientation relative to the apical to basolateral orientation, although no differential accumulation was noted between MDCK-WT and MDCK-MDR1 monolayers. Caco-2 monolayers demonstrated an approximate 2-fold increase in accumulation of MDMA. Exposure of various inhibitors of active drug transporters demonstrated mixed results; ritonavir, progesterone and indomethacin produced an approximately 50% reduction of MDMA transport, while verapamil, MK-571 and probenecid had no effect. Based on these data, it is concluded that MDMA efflux is mediated via the activity of a transporter distinct from P-glycoprotein. The possible inhibitory effects of amphetamines on rhodamine-123 transport were also assessed. MDMA, methylenedioxyamphetamine, amphetamine and methamphetamine, at physiologically relevant concentrations, did not significantly alter the transport of rhodamine-123 in Caco-2 monolayers or the LS180 cell line, suggesting that these compounds do not alter the function of P-glycoprotein.

Club Drugs and HIV Infection: A Review

Club drug use is common among populations with human immunodeficiency virus (HIV) and populations at high risk for HIV infection. Club drugs have a myriad of acute and chronic medical consequences. Club drug-related visits to the emergency department and admissions for treatment of substance use have increased dramatically over the past 15 years. Most epidemiological data support the role of club drugs in increasing sexual risk behavior, with some studies demonstrating an independent association between use of certain club drugs and HIV infection. The direct influence of club drugs on progression of HIV disease remains to be determined; however, club drugs may interact with certain retroviral medications and have been associated with decreased adherence to medication. Clinicians should ask all patients about patterns of club drug use, counsel patients about the risks associated with club drug use, and refer patients to appropriate behavioral treatment programs for substance use when clinically indicated.

From "Male Bonding Rituals" to "Suicide Tuesday": A qualitative study of issues faced by gay male ecstasy (MDMA) users

Use of MDMA and other club drugs has increased among gay men, but questions remain concerning the use, context, and popularity of these drugs; and views of their side effects. We interviewed in-depth 12 gay MDMA users in New York. MDMA had specific appeals to gay men, who often described isolation and stigmatization. Users underwent a period of initiation and social networks often became comprised of greater numbers of other users. Club environments fostered drug use and vice versa. Awareness of potential adverse effects varied and was minimized. Appropriate educational and prevention programs are needed to address these issues, and must take into account the specific contexts of these gay men's lives.

Recreational substance use and tolerance of efavirenz in HIV-1 infected patients

During the past few years, efavirenz has been increasingly used in the treatment of HIV1 infection. Its main side effect is a syndrome of central nervous system stimulation occurring in 40-50% of adults in the first few weeks of therapy which might be observed at increased frequency in subjects concurrently using recreational substances. We therefore conducted a single center, retrospective study in 134 patients treated with efavirenz and found no significant differences in CNS side effects or discontinuation rates between recreational substance (cocaine, ecstasy, cannabis) users and non-users. Although our study is limited, the results support the idea that efavirenz can be safely prescribed to patients using recreational substances.

Med-psych drug-drug interactions update. Antiretrovirals, part III: antiretrovirals and drugs of abuse

The third in a series reviewing the HIV/AIDS antiretroviral drugs, this report summarizes the interactions between antiretrovirals and common drugs of abuse. In an overview format for primary care physicians and psychiatrists, the metabolism and drug interactions in the context of antiretroviral therapy are presented for the following drugs of abuse: alcohol, benzodiazepines, cocaine, GHB (liquid X), ketamine (special K), LSD (acid), MDMA (Ecstasy), opiates, PCP (angel dust), and THC (marijuana).

Drug interactions in the management of HIV infection

The availability of antiretroviral therapy has significantly reduced the morbidity and mortality of HIV infection. In addition, improved treatment of opportunistic infections and comorbidities common to patients with HIV is further prolonging the lives of patients. Improvement in the treatment of HIV has led to a significant increase in the number of medications which caregivers are able to utilise to manage HIV/AIDS. Antiretroviral medications, as well as many of the drugs used in the management of opportunistic infections and primary care (e.g., macrolide antibiotics, azole antifungals, cholesterol-lowering medications), are particularly prone to drug interactions. The interpretation of clinically significant interactions is complicated by the rate at which new information on drug metabolism and transport is becoming available. Management of drug interactions in HIV is further confounded by conflicting study results and differences between documented and theoretical inter-actions. The mechanisms and significance of interactions involving antiretrovirals, drugs used for opportunistic infections, and other medications commonly used in HIV patients will be reviewed.