Pharmacokinetics and pharmacodynamics of 3,4-methylenedioxymethamphetamine (MDMA): interindividual differences due to polymorphisms and drug-drug interactions

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.

Interest and limits of using pharmacogenetics in MDMA-related fatalities: A case report

Interpreting postmortem concentrations of 3,4-Methylenedioxymethamphetamine (MDMA) remains challenging due to the wide range of reported results and the potential idiosyncratic nature of MDMA toxicity. Consequently, forensic pathologists often rely on a body of evidence to establish conclusions regarding the cause and the manner of death in death involving MDMA. Given these issues, implementing pharmacogenetics' (PGx)' testing may be beneficial. Here, this report discusses an MDMA-related fatality and explores the benefits and limitations of implementing pharmacogenetics (PGx) analysis in such cases. A 34-year-old white European male was found dead at home, lying naked on his bed in a state of marked rigor mortis. MDMA and methylenedioxyamphetamine were quantified using liquid chromatography coupled to tandem mass spectrometry at respectively 3800 and 170 µg/L in femoral blood. PGx analysis was performed on a peripheral blood sample collected in EDTA tube. Deep analysis of cytochrome P450 (CYP) 2D6, 1A2, 2B6, 2C19, 3A4 and catechol-O-methyltransferase (COMT) genes (including copy number variations analysis) was performed by Next Generation Sequencing (NGS) on an Illumina MiSeq® sequencer using the Pharmacogenomics community panel (SOPHIA genetics® x RNPGx). The data obtained was analyzed using Sophia DDM® software. PGx analysis revealed three variants in CYP2C19 (rs75087398, rs12248560 and rs11188072) resulting in a CYP2C19 * 1/* 17 genotype, predictive of a rapid metabolism phenotype, implying greater MDMA elimination. Additionally, two variants were found in the COMT gene (rs4633TT, rs4680AA). In the literature, carriers of rs4680AA or rs4680GA genotypes exhibit lower enzyme activity compared to those homozygous for the G allele. Low COMT activity level has been associated with increased MDMA cardiovascular effects and biological changes, including an increased risk of hyponatremia which is particularly relevant here regarding the potential mechanism of death. Despite these findings, there are currently too few available studies to draw any definitive conclusions, indicating a need for further research in this area to fully understand all the implications. Moreover, focusing solely on metabolic enzymes may not fully explain all the variability in MDMA toxicity. A holistic genetic approach is necessary, incorporating both metabolic enzymes and pharmacological targets, including serotonin, dopamine, and norepinephrine transporters and receptors.

Acute psychotropic, autonomic, and endocrine effects of 5,6-methylenedioxy-2-aminoindane (MDAI) compared with 3,4-methylenedioxymethamphetamine (MDMA) in human volunteers: A self-administration study

The acute psychoactive, autonomic, and endocrine effects of the new psychoactive substance (NPS) 5,6-methylenedioxy-2-aminoindane (MDAI; 3.0 mg/kg, range 180-228 mg) were investigated in six healthy volunteers (four males, two females) in a non-blinded fashion without placebo. Subjective, cardiovascular, and endocrine responses were compared with two different doses of 3,4-methylenedioxymethamphetamine (MDMA) (75 mg and 125 mg) described in previously published placebo-controlled studies, which used identical outcome measures including Visual Analogue Scales (VAS), the Adjective Mood Rating Scale (AMRS), and the 5 Dimensions of Altered States of Consciousness (5D-ASC) scale. MDAI was well tolerated and produced subjective effects comparable with those of 125 mg MDMA. MDAI increased blood pressure similar to 125 mg MDMA but did not increase heart rate or body temperature. MDAI increased cortisol and prolactin levels and could be detected in serum about 20 min post ingestion and remained detectable at least for 4 days. In urine, MDAI was detectable over a period of at least 6 days. Further clinical investigations are warranted to assess whether MDAI could serve as drug with medicinal properties.

Pharmacogenomics of 3,4-Methylenedioxymethamphetamine (MDMA): A Narrative Review of the Literature

3,4-Methylenedioxymethamphetamine (MDMA) is a synthetic amphetamine derivative with notable psychoactive properties and emerging therapeutic potential, particularly for treating post-traumatic stress disorders (PTSD) and substance use disorders. However, its use remains controversial due to inter-individual variability influenced by both environmental and genetic factors. In this context, pharmacogenomics could play a crucial role in guiding MDMA treatment by identifying individuals with genetic predispositions affecting their response to MDMA. Tailoring treatment plans based on individual's genetic makeup may enhance therapeutic outcomes and minimize adverse effects, leading to safer and more effective use of MDMA in clinical settings. Literature analysis reveals that the influence of genetic variants within genes encoded for enzymes involved in MDMA metabolism and/or pharmacodynamics (PD) targets have been relatively under-investigated in humans. Some studies have pointed out associations between MDMA-induced effects and polymorphisms. For example, the catechol-O-methyltransferase (COMT) Val158Met polymorphism has been associated with cognitive and cardiovascular MDMA-induced effects. Similarly, polymorphisms in the serotonin-linked promoter region (5HTTLPR) have been associated with several MDMA-induced adverse effects including mood disorders. However, despite these findings, only a few associations have been highlighted. Furthermore, some genes encoded for MDMA targets have been only poorly investigated, representing a significant research gap. These observations underscore the need for large-scale, controlled pharmacogenomics studies focusing on a broad panel of genes involved into MDMA pharmacokinetics and PD. Such studies could provide critical insights for optimizing MDMA's therapeutic use and minimizing its risks.

Drug-related deaths at Australian music festivals

BACKGROUND

Illicit drug use is overrepresented in music festival attendees compared with the general population. Drug use often involves a wide range of substances with the potential to cause drug toxicity. Law enforcement-centred strategies intended to deter drug use and supply at these mass gatherings have been implemented throughout Australia. However, many have been criticised for their lack of effectiveness, with evidence suggesting that they can inadvertently increase the risk of drug harm. Drug deaths are often multifactorial, providing added challenges in the development of prevention strategies. This study aimed to determine the frequency of deaths involving alcohol and other drugs at music festivals in Australia and to identify potential risk factors that may inform future harm reduction strategies.

METHODS

A descriptive case series study was conducted using the National Coronial Information System (NCIS) to investigate drug-related deaths at music festivals throughout Australia between 1 July 2000 (Queensland from 1 January 2001) and 31 December 2019, using a list of keywords comprising music festival names and terms.

RESULTS

There were 64 deaths, of which most involved males (73.4%) aged in their mid-20s (range 15-50 years). Drug toxicity was the most common primary cause of death (46.9%) followed by external injuries (37.5%). The drug most commonly detected or reported as being used was MDMA (65.6%), followed by alcohol (46.9%) and cannabis (17.2%), with most cases reporting the use of two or more drugs (including alcohol) and 36% reporting a history of drug misuse in the coroner's findings. Most deaths were unintentional, with less than a fifth of cases (17.2%) involving intentional self-harm. Clinical intervention was involved in 64.1% of cases and most festivals occurred in inner city locations (59.4%).

CONCLUSIONS

The findings suggest that drug-related deaths at music festivals in Australia typically involve young people using multiple illicit substances in combination with alcohol. Most are unintentional and could potentially be prevented through the implementation of a range of harm reduction strategies, including mobile medical care, drug checking services, and increased consumer education and awareness.

Neurological and cognitive alterations induced by MDMA in humans

3,4 Methylenedioxymethamphetamine generally referred to as MDMA or 'ecstasy' is a ring-substituted phenethylamine stimulant which produces powerful empathogenic effects. Use of MDMA remains popular despite prohibition, and potential long-term negative consequences of repeated use. MDMA produces its acute subjective effects primarily by stimulating the release of serotonin via action at the serotonin transporter (SERT). There is evidence that MDMA administration may lead to long lasting neurotoxic effects on serotonin neurons in primates, and reductions in markers of central serotonin axons, and axon terminals in animals. In humans, demonstration of serotonergic neurotoxicity is much more difficult to identify, and much of the research is complicated by confounding issues of polysubstance use, genetic and environmental factors and reliance on self-reports of previous drug use. We do not review the mechanisms for neurotoxicity in detail as they are covered elsewhere in this special issue. There is a large body of literature, however, which has investigated potential cognitive and neurocognitive consequences of repeated MDMA use. Here we review the literature on cognition, and neuroimaging studies that have investigated structural and functional brain changes associated with ecstasy use.

Ecstasy (3,4-methylenedioxymethamphetamine): Cardiovascular effects and mechanisms

3,4-methylenedioxymethamphetamine or MDMA (known as "ecstasy") is a recreational drug of abuse, popular worldwide for its distinctive psychotropic effects. Currently, the therapeutic potential of MDMA in psychotherapy has attracted a lot of interest from the scientific community, despite the multitude of effects that this drug of abuse elicits on the human body. While neuronal effects have been the most studied, cardiovascular effects have also been described, as increased blood pressure and heart rate are the most recognizable. However, other effects have also been described at the cardiac (impaired cardiac contractile function, arrhythmias, myocardial necrosis and valvular heart disease) and vascular (vasoconstriction, disruption of vascular integrity and altered haemostasis) levels. Several mechanisms have been proposed, from the interaction with monoamine transporters and receptors to the promotion of oxidative stress or the activation of matrix metalloproteinases (MMPs). This review provides an overview of the cardiovascular implications of MDMA intake and underlying mechanisms, relevant when considering its consumption as drug of abuse but also when considering its therapeutic potential in psychiatry. Moreover, the risk/benefit ratio of the therapeutic use of MDMA remains to be fully elucidated from a cardiovascular standpoint, particularly in patients with underlying cardiovascular disease.

Combining ecstasy and ethanol: higher risk for toxicity? A review

Ecstasy use is commonly combined with ethanol consumption. While combination drug use in general is correlated with a higher risk for toxicity, the risk of the specific combination of ecstasy (3,4-methylenedioxymethamphetamine (MDMA)) and ethanol is largely unknown. Therefore, we have reviewed the literature on changes in MDMA pharmacokinetics and pharmacodynamics due to concurrent ethanol exposure in human, animal and in vitro studies. MDMA pharmacokinetics appear unaffected: the MDMA blood concentration after concurrent exposure to MDMA and ethanol was comparable to lone MDMA exposure in multiple human placebo-controlled studies. In contrast, MDMA pharmacodynamics were affected: locomotor activity increased and body temperature decreased after concurrent exposure to MDMA and ethanol compared to lone MDMA exposure. Importantly, these additional ethanol effects were consistently observed in multiple animal studies. Additional ethanol effects have also been reported on other pharmacodynamic aspects, but are inconclusive due to a low number of studies or due to inconsistent findings. These investigated pharmacodynamic aspects include monoamine brain concentrations, neurological (psychomotor function, memory, anxiety, reinforcing properties), cardiovascular, liver and endocrine effects. Although only a single or a few studies were available investigating these aspects, most studies indicated an aggravation of MDMA-induced effects upon concurrent ethanol exposure. In summary, concurrent ethanol exposure appears to increase the risk for MDMA toxicity. Increased toxicity is due to an aggravation of MDMA pharmacodynamics, while MDMA pharmacokinetics is largely unaffected. Although a significant attenuation of the MDMA-induced increase of body temperature was observed in animal studies, its relevance for human exposure remains unclear.

MDMA Use by Paris Medical Students: Prevalence and Characteristics

3,4-Methylenedioxy-N-methylamphetamine (MDMA) is increasing being used by youth in Europe and in France, but characteristics of its use are unknown. Objectives: The aim was to characterize MDMA use in a sample of French medical students. Methods: Cross-sectional study of Paris VII medical students (N = 592) with an online self-reporting questionnaire. Results: 592 students completed the online questionnaire. 21.5% (n = 127) had experimented with MDMA. Use of MDMA was associated with male sex (p < 0.001), older age (p < 0.001), left the parent's home (p < 0.01), and belonging to a fraternity (p < 0.05). Most experimenters (90.7%) used MDMA in a club or during a music festival. Among users, 42.5% used it more than once a year and less than once a month. During the use, users drank alcohol (90.6%), smoked tobacco (70.9%), smoked cannabis (42.0%) or used cocaine (20.5%). In the days after the use, some smoked tobacco (40.9%), smoked cannabis (29.1%), drank alcohol (22.0%), used cocaine (1.6%) and also took benzodiazepines (5.5%). According to the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition, criteria, the prevalence of MDMA use disorder was 8.5% in our sample and 40.9% among MDMA users. As compared with students who never experienced MDMA, fewer users thought that occasional intake could be dangerous (66.9% vs 83.9%, p < 0.001) and that MDMA could be addictive (74.0% vs 90.3%, p < 0.001). Conclusions: Other studies focusing on drug consumption among students are necessary to define specific public health strategies of prevention and harmful reduction.

Toxicological analysis of serious drug-related harm among electronic dance music festival attendees in New South Wales, Australia: A consecutive case series

BACKGROUND

A substantial increase in drug-related harm was observed during the 2018-2019 music festival season in New South Wales, Australia, including the deaths of five young people. As part of a rapid public health response, the New South Wales Ministry of Health referred samples from patients with suspected severe drug-related illness for forensic toxicological testing to identify the type and concentration of substances associated with the presentations.

METHODS

Cases were identified through a variety of active and passive surveillance systems, and selected consecutively based on indicators of clinical severity. Comprehensive toxicology testing of blood and urine samples was expedited for all cases. Demographic and clinical characteristics were collated, together with quantitative toxicology results. Results were analysed using descriptive statistics.

RESULTS

Forty cases from eleven different music festivals were included. The majority of cases (80.0%) were aged 25 years and under. There were five fatalities, and 62.5% of cases were admitted to intensive care units. MDMA was the most frequent substance, detected in 87.5% of cases. In 82.9% of cases with MDMA, blood concentrations were above thresholds that have been associated with toxicity. Multiple substances were detected in 60.0% of cases. Novel psychoactive substances were not detected.

CONCLUSIONS

Our findings strongly suggest that MDMA-related toxicity was a major factor in the severity of the clinical presentations among these cases. Other substances may have enhanced MDMA toxicity but appear unlikely to have caused severe toxicity in isolation. These findings have important implications for harm reduction strategies targeted to music festival settings.

Differential effects of psychoactive substances on human wildtype and polymorphic T356M dopamine transporters (DAT)

Many psychoactive substances affect the human dopamine (DA) reuptake transporter (hDAT). Polymorphisms in the encoding gene could affect the functionality of the transporter and consequently alter effects of psychotropic and recreational drugs. Recently, a T356 M single nucleotide polymorphism in the human SLC6A3 gene was described, which resulted in functional impairments of DA uptake. Therefore, we investigated the effects of 10 psychoactive substances (0.01-1000 μM)) on DA uptake in human embryonic kidney (HEK) 293 cells transiently overexpressing wildtype (WT) or T356 M hDAT. Our data shows that T356 M hDAT has a 3 times lower V_max and a 3 times higher K_m compared to WT hDAT. Additionally, all psychoactive substances inhibited DA uptake by T356 M and WT hDAT. The DA reuptake inhibitors (methylphenidate, cocaine, and bupropion) inhibited DA uptake by WT hDAT most potently, followed by amphetamine-type stimulants [4-fluoroamphetamine (4-FA), amphetamine and MDMA], selective serotonin reuptake inhibitors (SSRI; fluoxetine and citalopram) and arylcyclohexylamines [methoxetamine (MXE) and ketamine]. Compared to DA uptake by WT hDAT, bupropion, methylphenidate, cocaine, and MXE less potently inhibited DA uptake by T356 M hDAT, while citalopram more potently inhibited uptake. The differences in IC₅₀ values between T356 M and WT hDAT were considerable (3-45 fold). As such, the presence of this polymorphism could affect treatment efficiency with these substances as well as susceptibly for toxicity and addiction for individuals carrying this polymorphism.

Identification and initial management of intoxication by alcohol and other drugs in the pediatric emergency room

OBJECTIVE

To review the screening, diagnosis, evaluation, and treatment of intoxication by alcohol and other drugs in children and adolescents in the emergency scenario.

DATA SOURCE

This was a narrative literature review.

DATA SUMMARY

The detection of this problem in the emergency room can be a challenge, especially when its assessment is not standardized. The intentional and episodic use of large amounts of psychoactive substances by adolescents is a usual occurrence, and unintentional intoxication is more common in children younger than 12 years. The clinical picture in adolescents and children differs from that in adults and some particularities are important in the emergency scenario. After management of the acute condition, interventions targeting the adolescent at risk may be effective.

CONCLUSION

The diagnosis and treatment of intoxication by alcohol and other drugs in adolescents and children in the emergency scenario requires a systematic evaluation of the use of these drugs. There are few specific treatments for intoxication, and the management comprehends support measures and management of related clinical complications.

Effect fingerprinting of new psychoactive substances (NPS): What can we learn from in vitro data?

The use of new psychoactive substances (NPS) is increasing and currently >600 NPS have been reported. However, limited information on neuropharmacological and toxicological effects of NPS is available, hampering risk characterization. We reviewed the literature on the in vitro neuronal modes of action to obtain effect fingerprints of different classes of illicit drugs and NPS. The most frequently reported NPS were selected for review: cathinones (MDPV, α-PVP, mephedrone, 4-MEC, pentedrone, methylone), cannabinoids (JWH-018), (hallucinogenic) phenethylamines (4-fluoroamphetamine, benzofurans (5-APB, 6-APB), 2C-B, NBOMes (25B-NBOMe, 25C-NBOMe, 25I-NBOMe)), arylcyclohexylamines (methoxetamine) and piperazine derivatives (mCPP, TFMPP, BZP). Our effect fingerprints highlight the main modes of action for the different NPS studied, including inhibition and/or reversal of monoamine reuptake transporters (cathinones and non-hallucinogenic phenethylamines), activation of 5-HT₂receptors (hallucinogenic phenethylamines and piperazines), activation of cannabinoid receptors (cannabinoids) and inhibition of NDMA receptors (arylcyclohexylamines). Importantly, we identified additional targets by relating reported effect concentrations to the estimated human brain concentrations during recreational use. These additional targets include dopamine receptors, α- and β-adrenergic receptors, GABA_Areceptors and acetylcholine receptors, which may all contribute to the observed clinical symptoms following exposure. Additional data is needed as the number of NPS continues to increase. Also, the effect fingerprints we have obtained are still incomplete and suffer from a large variation in the reported effects and effect sizes. Dedicated in vitro screening batteries will aid in complementing specific effect fingerprints of NPS. These fingerprints can be implemented in the risk assessments of NPS that are necessary for eventual control measures to reduce Public Health risks.

3,4-Methylenedioxymethamphetamine Increases Affiliative Behaviors in Squirrel Monkeys in a Serotonin 2A Receptor-Dependent Manner

3,4-Methylenedioxymethamphetamine (MDMA) increases sociality in humans and animals. Release of serotonin (5-HT) is thought to have an important role in the increase in social behaviors, but the mechanisms underlying these effects are poorly understood. Despite the advantages of nonhuman primate models, no studies have examined the mechanisms of the social effects of MDMA in nonhuman primates. The behavior and vocalizations of four group-housed squirrel monkeys were examined following administration of MDMA, its enantiomers, and methamphetamine. 5-HT receptor antagonists and agonists were given as drug pretreatments. Data were analyzed using linear mixed-effects models. MDMA and its enantiomers increased affiliative social behaviors and vocalizations, whereas methamphetamine had only modest effects on affiliative behaviors. Pretreatment with a 5-HT_2A receptor antagonist and a 5-HT_2C receptor agonist attenuated the MDMA-induced increase in social behaviors, while a 5-HT_1A receptor antagonist did not alter affiliative vocalizations and increased MDMA-induced social contact. Nonhuman primates show MDMA-specific increases in affiliative social behaviors following MDMA administration, in concordance with human and rodent studies. MDMA-induced increases in social behaviors are 5-HT_2A, but not 5-HT_1A, receptor dependent. Understanding the neurochemical mechanisms mediating the prosocial effects of MDMA could help in the development of novel therapeutics with the unique social effects of MDMA but fewer of its limitations.

The prognosis following amphetamine poisoning

Aims: This study investigated the long-term mortality following poisoning by amphetamine or substituted amphetamines. Furthermore, we examined the social problems and somatic and psychiatric co-morbidity related to amphetamine poisoning, and their impact on the long-term survival. Methods: We identified amphetamine poisoned patients from the Danish Poison Information Centre database and correlated their personal identification numbers with seven Danish national registries related to different social and health aspects. For each case, we sampled 100 age and gender matched controls from the background population. Results: From August 2006 to December 2013 we identified 1444 patients (70% males) who experienced amphetamine poisoning; 52% of the cases were classified as mixed poisonings and the average age at first contact was 24.8 years (SD 8.6). The prevalence of psychiatric disorders, HIV, viral hepatitis, and previous prison incarceration was approximately 10 times higher than among healthy controls. After seven years 11% were deceased as opposed to 0.6% in the control group, and 64% of the patients died from unnatural causes. Male gender (HR 2.29, 95% CI (1.07-4.90)), age (HR 1.06, 95% CI (1.03-1.09)), opioid dependence (HR 2.88, 95% CI (1.42-5.85)), schizophrenia (HR 3.09,95% CI (1.63-5.86)), affective disorders (HR 2.65, 95% CI (1.44-4.90)) and HIV (HR 5.45, 95% CI (1.19-24.90)) were associated with a high mortality. Furthermore, a significant proportion of these patients experienced social and health related deterioration in the years following poisoning. Conclusions: Amphetamine poisoning is associated with a poor long-term prognosis and is complicated by additional social and health related issues.

Measuring inhibition of monoamine reuptake transporters by new psychoactive substances (NPS) in real-time using a high-throughput, fluorescence-based assay

The prevalence and use of new psychoactive substances (NPS) is increasing and currently over 600 NPS exist. Many illicit drugs and NPS increase brain monoamine levels by inhibition and/or reversal of monoamine reuptake transporters (DAT, NET and SERT). This is often investigated using labor-intensive, radiometric endpoint measurements. We investigated the applicability of a novel and innovative assay that is based on a fluorescent monoamine mimicking substrate. DAT, NET or SERT-expressing human embryonic kidney (HEK293) cells were exposed to common drugs (cocaine, dl-amphetamine or MDMA), NPS (4-fluoroamphetamine, PMMA, α-PVP, 5-APB, 2C-B, 25B-NBOMe, 25I-NBOMe or methoxetamine) or the antidepressant fluoxetine. We demonstrate that this fluorescent microplate reader-based assay detects inhibition of different transporters by various drugs and discriminates between drugs. Most IC₅₀ values were in line with previous results from radiometric assays and within estimated human brain concentrations. However, phenethylamines showed higher IC₅₀ values on hSERT, possibly due to experimental differences. Compared to radiometric assays, this high-throughput fluorescent assay is uncomplicated, can measure at physiological conditions, requires no specific facilities and allows for kinetic measurements, enabling detection of transient effects. This assay is therefore a good alternative for radiometric assays to investigate effects of illicit drugs and NPS on monoamine reuptake transporters.

CYP2D6 function moderates the pharmacokinetics and pharmacodynamics of 3,4-methylene-dioxymethamphetamine in a controlled study in healthy individuals

Supplemental Digital Content is available in the text.

The role of genetic polymorphisms in cytochrome (CYP) 2D6 involved in the metabolism of 3,4-methylene-dioxymethamphetamine (MDMA, ecstasy) is unclear. Effects of genetic variants in CYP2D6 on the pharmacokinetics and pharmacodynamic effects of MDMA were characterized in 139 healthy individuals (70 men, 69 women) in a pooled analysis of eight double-blind, placebo-controlled crossover studies. In CYP2D6 poor metabolizers, the maximum concentrations (C_max) of MDMA and its active metabolite 3,4-methylene-dioxyamphetamine were +15 and +50% higher, respectively, compared with extensive metabolizers and the C_max of the inactive metabolite 4-hydroxy-3-methoxymethamphetamine was 50–70% lower. Blood pressure and subjective drug effects increased more rapidly after MDMA administration in poor metabolizers than in extensive metabolizers. In conclusion, the disposition of MDMA and its effects in humans are altered by polymorphic CYP2D6 activity, but the effects are small because of the autoinhibition of CYP2D6.

Pharmacogenetics of ecstasy: CYP1A2, CYP2C19, and CYP2B6 polymorphisms moderate pharmacokinetics of MDMA in healthy subjects

In vitro studies showed that CYP2C19, CYP2B6, and CYP1A2 contribute to the metabolism of 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) to 3,4-methylenedioxyamphetamine (MDA). However, the role of genetic polymorphisms in CYP2C19, CYP2B6, and CYP1A2 in the metabolism of MDMA in humans is unknown. The effects of genetic variants in these CYP enzymes on the pharmacokinetics and pharmacodynamics of MDMA were characterized in 139 healthy subjects (69 male, 70 female) in a pooled analysis of eight double-blind, placebo-controlled studies. MDMA-MDA conversion was positively associated with genotypes known to convey higher CYP2C19 or CYP2B6 activities. Additionally, CYP2C19 poor metabolizers showed greater cardiovascular responses to MDMA compared with other CYP2C19 genotypes. Furthermore, the maximum concentration of MDA was higher in tobacco smokers that harbored the inducible CYP1A2 rs762551 A/A genotype compared with the non-inducible C-allele carriers. The findings indicate that CYP2C19, CYP2B6, and CYP1A2 contribute to the metabolism of MDMA to MDA in humans. Additionally, genetic polymorphisms in CYP2C19 may moderate the cardiovascular toxicity of MDMA.

Treatment-refractory posttraumatic stress disorder (TRPTSD): a review and framework for the future

Post-traumatic stress disorder (PTSD) is a serious psychiatric consequence of trauma that occurs in a proportion of individuals exposed to life-threatening events. Trauma-focused psychotherapy is often recommended as first choice for those who do not recover spontaneously. But many individuals require medications. In the US, only paroxetine (PRX) and sertraline (SRT) are FDA approved for PTSD. But response and remission rates with these medications are low, so numerous other pharmacologic interventions have been tried. To date, there has not been a systematic review of the data on what are the best next-step pharmacologic strategies for individuals who fail standard treatments. To that end, we review 168 published trials of medications other than PRX or SRT and provide a detailed analysis of the 88/168 studies that describe alternative pharmacologic interventions in patients refractory to other treatment. We also review clinical factors relevant to treatment-refractory PTSD; the neurobiology of extinction, as well as evidence-based psychotherapy and neuromodulation strategies for this condition.

Tamoxifen and amphetamine abuse: Are there therapeutic possibilities?

Although best known as a selective estrogen receptor modulator (SERM), tamoxifen is a drug with a wide range of activities. Tamoxifen has demonstrated some efficacy has a therapeutic for bipolar mania and is believed to exert these effects through inhibition of protein kinase C (PKC). As the symptoms of amphetamine treatment in rodents are believed to mimic the symptoms of a manic episode, many of the preclinical studies for this indication have demonstrated that tamoxifen inhibits amphetamine action. The amphetamine-induced increase in extracellular dopamine which gives rise to the 'manic' effects is due to interaction of amphetamine with the dopamine transporter. We and others have demonstrated that PKC reduces amphetamine-induced reverse transport through the dopamine transporter. In this review, we will outline the actions of tamoxifen as a SERM and further detail another known action of tamoxifen-inhibition of PKC. We will summarize the literature showing how tamoxifen affects amphetamine action. Finally, we will present our hypothesis that tamoxifen, or an analog, could be used therapeutically to reduce amphetamine abuse in addition to treating mania.

Impact of Cytochrome P450 2D6 Function on the Chiral Blood Plasma Pharmacokinetics of 3,4-Methylenedioxymethamphetamine (MDMA) and Its Phase I and II Metabolites in Humans

3,4-methylenedioxymethamphetamine (MDMA; ecstasy) metabolism is known to be stereoselective, with preference for S-stereoisomers. Its major metabolic step involves CYP2D6-catalyzed demethylenation to 3,4-dihydroxymethamphetamine (DHMA), followed by methylation and conjugation. Alterations in CYP2D6 genotype and/or phenotype have been associated with higher toxicity. Therefore, the impact of CYP2D6 function on the plasma pharmacokinetics of MDMA and its phase I and II metabolites was tested by comparing extensive metabolizers (EMs), intermediate metabolizers (IMs), and EMs that were pretreated with bupropion as a metabolic inhibitor in a controlled MDMA administration study. Blood plasma samples were collected from 16 healthy participants (13 EMs and three IMs) up to 24 h after MDMA administration in a double-blind, placebo-controlled, four-period, cross-over design, with subjects receiving 1 week placebo or bupropion pretreatment followed by a single placebo or MDMA (125 mg) dose. Bupropion pretreatment increased the maximum plasma concentration (C_max) and area under the plasma concentration-time curve from 0 to 24 h (AUC₂₄) of R-MDMA (9% and 25%, respectively) and S-MDMA (16% and 38%, respectively). Bupropion reduced the C_max and AUC₂₄ of the CYP2D6-dependently formed metabolite stereoisomers of DHMA 3-sulfate, DHMA 4-sulfate, and 4-hydroxy-3-methoxymethamphetamine (HMMA sulfate and HMMA glucuronide) by approximately 40%. The changes that were observed in IMs were generally comparable to bupropion-pretreated EMs. Although changes in stereoselectivity based on CYP2D6 activity were observed, these likely have low clinical relevance. Bupropion and hydroxybupropion stereoisomer pharmacokinetics were unaltered by MDMA co-administration. The present data might aid further interpretations of toxicity based on CYP2D6-dependent MDMA metabolism.

Is toxicity of PMMA (paramethoxymethamphetamine) associated with cytochrome P450 pharmacogenetics?

In 2010-2013, 29 fatal intoxications related to the designer drug paramethoxymethamphetamine (PMMA, 4-methoxymethamphetamine) occurred in Norway. The current knowledge about metabolism and toxicity of PMMA in humans is limited. Metabolism by the polymorphic cytochrome P450 (CYP) 2D6 enzyme to the psychoactive metabolite 4-hydroxymethamphetamine (OH-MA), and possibly by additional enzymes, is suggested to be involved in its toxicity. The aim of this work was to study the association between CYP genetics, PMMA metabolism and risk of fatal PMMA toxicity in humans. The frequency distribution of clinically relevant gene variants of CYP2D6, CYP2C9, CYP2C19 and CYP3A5, and the phenotypic blood CYP2D6 metabolic ratio (OH-MA/PMMA) in particular, were compared in fatal PMMA intoxications (n=17) and nonfatal PMMA abuse controls (n=30), using non-abusers (n=305) as references for the expected genotype frequencies in the Norwegian population. Our study demonstrated that the CYP2D6 enzyme and genotype are important in the metabolism of PMMA to OH-MA in humans, but that other enzymes are also involved in this biotransformation. In the fatal PMMA intoxications, the blood concentrations of PMMA were higher and the CYP2D6 metabolic ratios were lower, than in the nonfatal PMMA abuse controls (median (range) 2.1 (0.03-5.0) vs 0.3 (0.1-0.9) mg/L, and ratio 0.6 (0.0-4.6) vs 2.1 (0.2-7.4) p=0.021, respectively). Overall, our findings indicated that, in most cases, PMMA death occurred rapidly and at an early stage of PMMA metabolism, following the ingestion of large and toxic PMMA doses. We could not identify any genetic CYP2D6, CYP2C9, CYP2C19 or CYP3A5 predictive marker on fatal toxicity of PMMA in humans. The overrepresentation of the CYP2D6 poor metabolizer (PM) genotype found in the nonfatal PMMA abuse controls warrants further investigations.

High-mesembrine Sceletium extract (Trimesemine™) is a monoamine releasing agent, rather than only a selective serotonin reuptake inhibitor

ETHNOPHARMACOLOGICAL RELEVANCE

Extracts from and alkaloids contained in plants in the genus Sceletium have been reported to inhibit ligand binding to serotonin transporter. From this, the conclusion was made that Sceletium products act as selective serotonin-reuptake inhibitors. However, other mechanisms which may similarly result in the anxiolytic or anti-depressant effect ascribed to Sceletium, such as monoamine release, have not been investigated.

AIMS OF THE STUDY

The current study investigated simultaneously and at two consecutive time points, the effect of high-mesembrine Sceletium extract on both monoamine release and serotonin reuptake into both human astrocytes and mouse hippocampal neurons, as well as potential inhibitory effects on relevant enzyme activities.

MATERIALS AND METHODS

Human astrocytes and mouse hippocampal cells were treated with citalopram or Sceletium extract for 15 and 30min, after which protein expression levels of serotonin transporter (SERT) and vesicular monoamine transporter-2 (VAMT-2) was assessed using fluorescent immunocytochemistry and digital image analysis. Efficacy of inhibition of acetylcholinesterase (AChE) and monoamine oxidate-A (MAO-A) activity were assessed using the Ellman and Olsen methods (and appropriate controls) respectively.

RESULTS

We report the first investigation of mechanism of action of Sceletium extract in the context of serotonin transport, release and reuptake in a cellular model. Cell viability was not affected by Sceletium treatment. High-mesembrine Sceletium extract down-regulated SERT expression similarly to citalopram. In addition, VMAT-2 was upregulated significantly in response to Sceletium treatment. The extract showed only relatively mild inhibition of AChE and MAO-A.

CONCLUSIONS

We conclude that the serotonin reuptake inhibition activity ascribed to the Sceletium plant, is a secondary function to the monoamine-releasing activity of high-mesembrine Sceletium extract (Trimesemine(TM)).

Effect of MDMA-Induced Axotomy on the Dorsal Raphe Forebrain Tract in Rats: An In Vivo Manganese-Enhanced Magnetic Resonance Imaging Study

3,4-Methylenedioxymethamphetamine (MDMA), also known as “Ecstasy”, is a common recreational drug of abuse. Several previous studies have attributed the central serotonergic neurotoxicity of MDMA to distal axotomy, since only fine serotonergic axons ascending from the raphe nucleus are lost without apparent damage to their cell bodies. However, this axotomy has never been visualized directly in vivo. The present study examined the axonal integrity of the efferent projections from the midbrain raphe nucleus after MDMA exposure using in vivo manganese-enhanced magnetic resonance imaging (MEMRI). Rats were injected subcutaneously six times with MDMA (5 mg/kg) or saline once daily. Eight days after the last injection, manganese ions (Mn²⁺) were injected stereotactically into the raphe nucleus, and a series of MEMRI images was acquired over a period of 38 h to monitor the evolution of Mn²⁺-induced signal enhancement across the ventral tegmental area, the medial forebrain bundle (MFB), and the striatum. The MDMA-induced loss of serotonin transporters was clearly evidenced by immunohistological staining consistent with the Mn²⁺-induced signal enhancement observed across the MFB and striatum. MEMRI successfully revealed the disruption of the serotonergic raphe-striatal projections and the variable effect of MDMA on the kinetics of Mn²⁺ accumulation in the MFB and striatum.

Hallucinogen persisting perception disorder and the serotonergic system: a comprehensive review including new MDMA-related clinical cases

Hallucinogen persisting perception disorder (HPPD) is a drug-induced condition associated with inaccurate visual representations. Since the underlying mechanism(s) are largely unknown, this review aims to uncover aspects underlying its etiology. Available evidence on HPPD and drug-related altered visual processing was reviewed and the majority of HPPD cases were attributed to drugs with agonistic effects on serotonergic 5-HT₂A receptors. Moreover, we present 31 new HPPD cases that link HPPD to the use of ecstasy (MDMA), which is known to reverse serotonin reuptake and acts as agonist on 5-HT₂A receptors. The available evidence suggests that HPPD symptoms may be a result from a misbalance of inhibitory-excitatory activity in low-level visual processing and GABA-releasing inhibitory interneurons may be involved. However, high co-morbidities with anxiety, attention problems and derealization symptoms add complexity to the etiology of HPPD. Also, other perceptual disorders that show similarity to HPPD cannot be ruled out in presentations to clinical treatment. Taken together, evidence is still sparse, though low-level visual processing may play an important role. A novel finding of this review study, evidenced by our new cases, is that ecstasy (MDMA) use may also induce symptoms of HPPD.

Nephrotoxic effects of common and emerging drugs of abuse

The kidneys can be injured in diverse ways by many drugs, both legal and illegal. Novel associations and descriptions of nephrotoxic effects of common and emerging drugs of abuse have appeared over the past several years. Anabolic androgenic steroids, illicitly used by athletes and others for decades to increase muscle mass and decrease body fat, are emerging as podocyte toxins given recent descriptions of severe forms of FSGS in long-term abusers. Synthetic cannabinoids, a new group of compounds with marijuana-like effects, recently became popular as recreational drugs and have been associated with an atypical form of AKI. 3,4-Methylenedioxymethamphetamine, commonly known as ecstasy, is a widely used synthetic recreational drug with mood-enhancing properties and a constellation of toxicities that can result in death. These toxic effects include hyperthermia, hypotonic hyponatremia due to its arginine vasopressin secretagogue-like effects, rhabdomyolysis, and cardiovascular collapse. Cocaine, a serotonin-norepinephrine-dopamine reuptake inhibitor that serves as an illegal stimulant, appetite suppressant, and anesthetic, also causes vasoconstriction and rhabdomyolysis. Recent adulteration of much of the world's supply of cocaine with levamisole, an antihelminthic agent with attributes similar to but distinct from those of cocaine, appears to have spawned a new type of ANCA-associated systemic vasculitis. This review discusses the nephrotoxic effects of these common and emerging drugs of abuse, of which both community and health care providers should become aware given their widespread abuse. Future investigation into pathogenetic mechanisms associated with these drugs is critical and may provide a window into ways to lessen and even prevent the nephrotoxic effects of these drugs of abuse and perhaps allow a deeper understanding of the nephrotoxicities themselves.

3,4-Methylenedioxymethamphetamine’s (MDMA’s) Impact on Posttraumatic Stress Disorder

Objective: Review the current literature assessing the role of 3,4-methylenedioxymethamphetamine (MDMA) on posttraumatic stress disorder (PTSD). Data Sources: OVID MEDLINE search (1960-February 2014) using the terms MDMA, 3,4-methylenedioxymethamphetamine, Molly, and Ecstasy crossed with posttraumatic stress disorder with backwards citation tracking using references from procured articles. Study Selection and Data Extraction: English language studies assessing MDMA in patients with PTSD. Data Synthesis: Three randomized controlled trials (RCTs) were conducted along with follow-up open-label and extension evaluations. In the 3 RCTs, therapy with MDMA-assisted psychotherapy is promising, with reductions in PTSD rating scale scores (Clinician-Administered PTSD Scale, Severity of Symptoms Scale for PTSD Scale), although 2 of 3 trials did not show significant results, and all three had methodological limitations. The direction of effect for all trials was toward benefit in patients who were refractory to other PTSD therapies; the percentage reductions on rating scores ranged from 23% to 68%; and in 1 trial, the effect was sustained over a long period of time. MDMA ingestion without sustained psychotherapy over a 6- to 8-hour period is unlikely to be beneficial; trying to prolong the duration of effect with supplemental dosing is unlikely to provide additional benefits; and there are adverse effects on blood pressure and heart rate that should be appreciated. These studies used unadulterated MDMA with known and reproducible potency, which may not happen with street purchase of the product. Conclusions: MDMA-assisted psychotherapy may be an effective therapy in refractory PTSD but needs further evaluation to determine its place in contemporary therapy.