Physiological and subjective responses to controlled oral 3,4-methylenedioxymethamphetamine administration

The entactogen 3,4-methylenedioxymethamphetamine (MDMA; ecstasy) as a treatment aid in psychotherapy and its safety concerns

The phenylethylamine, 3,4-methylenedioxymethamphetamine (MDMA, 'ecstasy'), is the prototypical example of an entactogen. Its original placement in highly restrictive drug usage categories in the US and UK, led to an inevitable restriction on MDMA neuroscience research and treatment. The dominant pharmacological effects of MDMA are its properties of release and inhibition of reuptake of amine neurotransmitter transporters for dopamine, norepinephrine, and serotonin. MDMA is an agonist of a wide range of receptors; its mood-altering effects are mediated via 5-HT2A receptors; this receptor may also mediate its effects on body temperature, analgesia, and anxiolytic properties. The mechanisms underlying MDMA's entactogenic properties of sociability and interpersonal closeness are not known but release and involvement of oxytocin, a peptide thought by some to be involved in social bonding, has been suggested. Adverse effects of MDMA are mostly transient; acute multiorgan adverse effects occurring during raves or crowded dance gatherings include dehydration, hyperthermia, seizures, rhabdomyolysis, disseminated intravascular coagulation, and acute renal failure. Deaths following MDMA taken by itself are rare compared to fatalities following coadministration with other drugs. A recent FDA-approved phase 3 clinical trial of MDMA for post-traumatic stress disorder (PTSD) led to the conclusion that MDMA-assisted therapy represents a potential breakthrough treatment meriting expedited clinical evaluation. Despite the ongoing deliberations by the FDA and EMA for approval of MDMA treatment of PTSD, the Australian Therapeutic Goods Administration (TGA) recently announced that after an evaluation of the therapeutic value, benefits, and risks of MDMA, it will permit its prescribing for the treatment of PTSD. Further examples of regulatory relaxation toward MDMA-assisted psychotherapy are underway. These include the FDA's recently approved clinical trial to assess MDMA's efficacy in the treatment of "asociality" in patients with schizophrenia and an open trial of MDMA treatment for alcohol-use disorder which showed decreased alcohol consumption. There are also ongoing studies on the little understood startle response, anxiety associated with life-threatening illness, and social anxiety in autistic adults.

Effect of MDMA-assisted therapy on mood and anxiety symptoms in advanced-stage cancer (EMMAC): study protocol for a double-blind, randomised controlled trial

BACKGROUND

Symptoms of anxiety and depression are common in patients with terminal illness and multiple challenges exist with timely and effective care in this population. Several centres have reported that one dose of the serotonergic psychedelic psilocybin, combined with therapeutic support, improves these symptoms for up to 6 months in this patient group. Drawing upon related therapeutic mechanisms, 3,4-methylenedioxymethamphetamine (MDMA)-assisted therapy may have the potential to achieve similar, positive mental health outcomes in this group. Preliminary evidence also supports the tolerability of MDMA-assisted therapy for anxiety and depression in advanced-stage cancer.

METHODS

Up to 32 participants with advanced-stage cancer and associated depression and anxiety will be randomised in a 1:1 ratio into one of two blinded parallel treatment arms. The intervention group will receive 120 mg (+ 60 mg optional supplemental dose) MDMA-assisted therapy. The psychoactive control group will receive 20 mg oral (+ 10 mg optional supplemental dose) methylphenidate-assisted therapy. For each medication-assisted therapy session, participants will undergo two 90-min therapeutic support sessions in the week preceding, and one 90-min support session the day after the experimental session. A battery of measures (mood, anxiety, quality of life, mystical experience, spiritual wellbeing, attitudes towards death, personality traits, holistic health and wellbeing, connectedness, demoralisation, expectations, qualitative data and safety measures) will be assessed at baseline and through to the end of the protocol. Participants will be followed up until either 12 months post-randomisation or death, whichever occurs first.

DISCUSSION

This study will examine the effect of MDMA-assisted therapy on symptoms of anxiety and depression in advanced-stage cancer. Potential therapeutic implications include establishing the safety and effectiveness of a novel treatment that may relieve mental suffering in patients with life-threatening illness.

TRIAL REGISTRATION

Trial registered on Australian New Zealand Clinical Trials Registry.

REGISTRATION NUMBER

ACTRN12619001334190p. Date registered: 30/09/2019. URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=378153&showOriginal=true&isReview=true.

The Psychedelic Future of Post-Traumatic Stress Disorder Treatment

Post-traumatic stress disorder (PTSD) is a mental health condition that can occur following exposure to a traumatic experience. An estimated 12 million U.S. adults are presently affected by this disorder. Current treatments include psychological therapies (e.g., exposure-based interventions) and pharmacological treatments (e.g., selective serotonin reuptake inhibitors (SSRIs)). However, a significant proportion of patients receiving standard-of-care therapies for PTSD remain symptomatic, and new approaches for this and other trauma-related mental health conditions are greatly needed. Psychedelic compounds that alter cognition, perception, and mood are currently being examined for their efficacy in treating PTSD despite their current status as Drug Enforcement Administration (DEA)- scheduled substances. Initial clinical trials have demonstrated the potential value of psychedelicassisted therapy to treat PTSD and other psychiatric disorders. In this comprehensive review, we summarize the state of the science of PTSD clinical care, including current treatments and their shortcomings. We review clinical studies of psychedelic interventions to treat PTSD, trauma-related disorders, and common comorbidities. The classic psychedelics psilocybin, lysergic acid diethylamide (LSD), and N,N-dimethyltryptamine (DMT) and DMT-containing ayahuasca, as well as the entactogen 3,4-methylenedioxymethamphetamine (MDMA) and the dissociative anesthetic ketamine, are reviewed. For each drug, we present the history of use, psychological and somatic effects, pharmacology, and safety profile. The rationale and proposed mechanisms for use in treating PTSD and traumarelated disorders are discussed. This review concludes with an in-depth consideration of future directions for the psychiatric applications of psychedelics to maximize therapeutic benefit and minimize risk in individuals and communities impacted by trauma-related conditions.

Psychedelics reopen the social reward learning critical period

Psychedelics are a broad class of drugs defined by their ability to induce an altered state of consciousness1,2. These drugs have been used for millennia in both spiritual and medicinal contexts, and a number of recent clinical successes have spurred a renewed interest in developing psychedelic therapies3-9. Nevertheless, a unifying mechanism that can account for these shared phenomenological and therapeutic properties remains unknown. Here we demonstrate in mice that the ability to reopen the social reward learning critical period is a shared property across psychedelic drugs. Notably, the time course of critical period reopening is proportional to the duration of acute subjective effects reported in humans. Furthermore, the ability to reinstate social reward learning in adulthood is paralleled by metaplastic restoration of oxytocin-mediated long-term depression in the nucleus accumbens. Finally, identification of differentially expressed genes in the 'open state' versus the 'closed state' provides evidence that reorganization of the extracellular matrix is a common downstream mechanism underlying psychedelic drug-mediated critical period reopening. Together these results have important implications for the implementation of psychedelics in clinical practice, as well as the design of novel compounds for the treatment of neuropsychiatric disease.

The promise of psychedelic research

The use of psychedelics as medicines and for overall better brain health is potentially one of the most transformative developments given their immediate and long-lasting therapeutic effects across a plethora of neuropsychiatric disorders and, more recently, some neurodegenerative diseases. The US psychedelic drugs market is forecasted to grow by 16.3% by 2027 due to the increasing prevalence of treatment-resistant depression and mental health disorders. Decades-long restrictions, which date back to when psychedelics were declared controlled substances in 1970, have been lifted to allow researchers to publish on the therapeutic benefits of psychedelics. This review will feature the incredible depth of research underway revealing how psychedelics impact brain structure and function to treat mental health and other neurological disorders.

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.

Beyond ecstasy: Alternative entactogens to 3,4-methylenedioxymethamphetamine with potential applications in psychotherapy

The last two decades have seen a revival of interest in the entactogen 3,4-methylenedioxy-N-methylamphetamine (MDMA) as an adjunct to psychotherapy, particularly for the treatment of post-traumatic stress disorder. While clinical results are highly promising, and MDMA is expected to be approved as a treatment in the near future, it is currently the only compound in its class of action that is being actively investigated as a medicine. This lack of alternatives to MDMA may prove detrimental to patients who do not respond well to the particular mechanism of action of MDMA or whose treatment calls for a modification of MDMA's effects. For instance, patients with existing cardiovascular conditions or with a prolonged history of stimulant drug use may not fit into the current model of MDMA-assisted psychotherapy, and could benefit from alternative drugs. This review examines the existing literature on a host of entactogenic drugs, which may prove to be useful alternatives in the future, paying particularly close attention to any neurotoxic risks, neuropharmacological mechanism of action and entactogenic commonalities with MDMA. The substances examined derive from the 1,3-benzodioxole, cathinone, benzofuran, aminoindane, indole and amphetamine classes. Several compounds from these classes are identified as potential alternatives to MDMA.

Prediction of MDMA response in healthy humans: a pooled analysis of placebo-controlled studies

BACKGROUND

3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") is used both recreationally and therapeutically. Little is known about the factors influencing inter- and intra-individual differences in the acute response to MDMA. Effects of other psychoactive substances have been shown to be critically influenced by personality traits and mood state before intake.

METHODS

We pooled data from 10 randomized, double-blind, placebo-controlled, cross-over studies performed in the same laboratory in 194 healthy subjects receiving doses of 75 or 125mg of MDMA. We investigated the influence of drug dose, body weight, sex, age, drug pre-experience, genetics, personality and mental state before drug intake on the acute physiological and psychological response to MDMA.

RESULTS

In univariable analyses, the MDMA plasma concentration was the strongest predictor for most outcome variables. When adjusting for dose per body weight, we found that (a) a higher activity of the enzyme CYP2D6 predicted lower MDMA plasma concentration, (b) a higher score in the personality trait "openness to experience" predicted more perceived "closeness", a stronger decrease in "general inactivation", and higher scores in the 5D-ASC (5 Dimensions of Altered States of Consciousness Questionnaire) scales "oceanic boundlessness" and "visionary restructuralization", and (c) subjects with high "neuroticism" or trait anxiety were more likely to have unpleasant and/or anxious reactions.

CONCLUSIONS

Although MDMA plasma concentration was the strongest predictor, several personality traits and mood state variables additionally explained variance in the response to MDMA. The results confirm that both pharmacological and non-pharmacological variables influence the response to MDMA. These findings may be relevant for the therapeutic use of MDMA.

A Systematic Review of the MDMA Model to Address Social Impairment in Autism

BACKGROUND

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder characterised by repetitive behaviours, cognitive rigidity/inflexibility, and social-affective impairment. Unfortunately, no gold-standard treatments exist to alleviate the core socio-behavioural impairments of ASD. Meanwhile, the prosocial empathogen/entactogen 3,4-methylene-dioxy-methamphetamine (MDMA) is known to enhance sociability and empathy in both humans and animal models of psychological disorders.

OBJECTIVE

We review the evidence obtained from behavioural tests across the current literature, showing how MDMA can induce prosocial effects in animals and humans, where controlled experiments were able to be performed.

METHODS

Six electronic databases were consulted. The search strategy was tailored to each database. Only English-language papers were reviewed. Behaviours not screened in this review may have affected the core ASD behaviours studied. Molecular analogues of MDMA have not been investigated.

RESULTS

We find that the social impairments may potentially be alleviated by postnatal administration of MDMA producing prosocial behaviours in mostly the animal model.

CONCLUSION

MDMA and/or MDMA-like molecules appear to be an effective pharmacological treatment for the social impairments of autism, at least in animal models. Notably, clinical trials based on MDMA use are now in progress. Nevertheless, larger and more extended clinical studies are warranted to prove the assumption that MDMA and MDMA-like molecules have a role in the management of the social impairments of autism.

Dark Classics in Chemical Neuroscience: 3,4-Methylenedioxymethamphetamine

Better known as "ecstasy", 3,4-methylenedioxymethamphetamine (MDMA) is a small molecule that has played a prominent role in defining the ethos of today's teenagers and young adults, much like lysergic acid diethylamide (LSD) did in the 1960s. Though MDMA possesses structural similarities to compounds like amphetamine and mescaline, it produces subjective effects that are unlike any of the classical psychostimulants or hallucinogens and is one of the few compounds capable of reliably producing prosocial behavioral states. As a result, MDMA has captured the attention of recreational users, the media, artists, psychiatrists, and neuropharmacologists alike. Here, we detail the synthesis of MDMA as well as its pharmacology, metabolism, adverse effects, and potential use in medicine. Finally, we discuss its history and why it is perhaps the most important compound for the future of psychedelic science-having the potential to either facilitate new psychedelic research initiatives, or to usher in a second Dark Age for the field.

Gene expression analysis indicates reduced memory and cognitive functions in the hippocampus and increase in synaptic reorganization in the frontal cortex 3 weeks after MDMA administration in Dark Agouti rats

BACKGROUND

3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") is a widely used entactogenic drug known to impair cognitive functions on the long-run. Both hippocampal and frontal cortical regions have well established roles in behavior, memory formation and other cognitive tasks and damage of these regions is associated with altered behavior and cognitive functions frequently described in otherwise healthy MDMA users. Meanwhile, in post-traumatic stress disorder (PTSD) patients seem to benefit from therapeutic application of the drug, where damage in hippocampal cue extinction may play a role. The aim of this study was to examine the hippocampus, frontal cortex and dorsal raphe of Dark Agouti rats with gene expression arrays (Illumina RatRef bead arrays) looking for possible mechanisms and new candidates contributing to the consequences of a single dose of MDMA (15 mg/kg) 3 weeks earlier.

RESULTS

The number of differentially expressed genes in the hippocampus, frontal cortex and the dorsal raphe were 481, 155, and 15, respectively. Gene set enrichment analysis of the microarray data revealed reduced expression of 'memory' and 'cognition', 'dendrite development' and 'regulation of synaptic plasticity' gene sets in the hippocampus, parallel to the downregulation of CaMK II subunits, glutamate-, CB1 cannabinoid- and EphA4, EphA5, EphA6 receptors. Downregulated gene sets in the frontal cortex were related to protein synthesis, chromatin organization, transmembrane transport processes, while 'dendrite development', 'regulation of synaptic plasticity' and 'positive regulation of synapse assembly' gene sets were upregulated besides elevated levels of a CaMK II subunit and NMDA2B glutamate receptor. Changes in the dorsal raphe region were mild and in most cases not significant.

CONCLUSION

The present data raise the possibility of new synapse formation / synaptic reorganization in the frontal cortex 3 weeks after a single neurotoxic dose of MDMA. In contrast, a prolonged depression of new neurite formation in the hippocampus is proposed by downregulations of members in long-term potentiation pathway and synaptic plasticity emphasizing the particular vulnerability of this brain region and proposing a mechanism responsible for cognitive problems in healthy individuals. At the same time, these results underpin benefits of MDMA in PTSD, where the drug may help memory extinction.

(±)-MDMA and its enantiomers: potential therapeutic advantages of R(-)-MDMA

The use of (±)-3,4-methylenedioxymethamphetamine ((±)-MDMA) as an adjunct to psychotherapy in the treatment of psychiatric and behavioral disorders dates back over 50 years. Only in recent years have controlled and peer-reviewed preclinical and clinical studies lent support to (±)-MDMA's hypothesized clinical utility. However, the clinical utility of (±)-MDMA is potentially mitigated by a range of demonstrated adverse effects. One potential solution could lie in the individual S(+) and R(-) enantiomers that comprise (±)-MDMA. Individual enantiomers of racemic compounds have been employed in psychiatry to improve a drug's therapeutic index. Although no research has explored the individual effects of either S(+)-MDMA or R(-)-MDMA in humans in a controlled manner, preclinical research has examined similarities and differences between the two molecules and the racemic compound. This review addresses information related to the pharmacodynamics, neurotoxicity, physiological effects, and behavioral effects of S(+)-MDMA and R(-)-MDMA that might guide preclinical and clinical research. The current preclinical evidence suggests that R(-)-MDMA may provide an improved therapeutic index, maintaining the therapeutic effects of (±)-MDMA with a reduced side effect profile, and that future investigations should investigate the therapeutic potential of R(-)-MDMA.

Safety pharmacology of acute MDMA administration in healthy subjects

3,4-Methylenedioxymethamphetamine (MDMA; ecstasy) is being investigated in MDMA-assisted psychotherapy. The present study characterized the safety pharmacology of single-dose administrations of MDMA (75 or 125 mg) using data from nine double-blind, placebo-controlled, crossover studies performed in the same laboratory in a total of 166 healthy subjects. The duration of the subjective effects was 4.2 ± 1.3 h (range: 1.4-8.2 h). The 125 mg dose of MDMA produced greater 'good drug effect' ratings than 75 mg. MDMA produced moderate and transient 'bad drug effect' ratings, which were greater in women than in men. MDMA increased systolic blood pressure to >160 mmHg, heart rate >100 beats/min, and body temperature >38°C in 33%, 29% and 19% of the subjects, respectively. These proportions of subjects with hypertension (>160 mmHg), tachycardia, and body temperature >38°C were all significantly greater after 125 mg MDMA compared with the 75 mg dose. Acute and subacute adverse effects of MDMA as assessed by the List of Complaints were dose-dependent and more frequent in females. MDMA did not affect liver or kidney function at EOS 29 ± 22 days after use. No serious adverse events occurred. In conclusion, MDMA produced predominantly acute positive subjective drug effects. Bad subjective drug effects and other adverse effects were significantly more common in women. MDMA administration was overall safe in physically and psychiatrically healthy subjects and in a medical setting. However, the risks of MDMA are likely higher in patients with cardiovascular disease and remain to be investigated in patients with psychiatric disorders.

Contractile effects of 3,4-methylenedioxymethamphetamine on the human internal mammary artery

Since the late 1980s numerous reports have detailed adverse reactions to the use of 3,4-methylenedioxymethamphetamine (MDMA) associated with cardiovascular collapse and sudden death, following ventricular tachycardia and hypertension. For a better understanding of the effects of MDMA on the cardiovascular system, it is critical to determine their effects at the vasculature level, including the transporter or neurotransmitter systems that are most affected at the whole range of drug doses. With this purpose in mind, the aim of our study was to evaluate the contractile effect of MDMA in the human internal mammary artery, the contribution of SERT for this effect and the responsiveness of this artery to 5-HT in the presence of MDMA. We have also studied the possible involvement of 5-HT2 receptors on the MDMA contractile effect in this human blood vessel using ketanserin. Our results showed that MDMA contracted the studied human's internal mammary artery in a SERT-independent form, through activation of 5-HT2A receptors. Considering the high plasma concentrations achieved in heavy users or in situations of acute exposure to drugs, this effect is probably involved in the cardiovascular risk profile of this psychostimulant, especially in subjects with pre-existing cardiovascular disease.

The prosocial effects of 3,4-methylenedioxymethamphetamine (MDMA): Controlled studies in humans and laboratory animals

Users of ±3,4-methylenedioxymethamphetamine (MDMA; 'ecstasy') report prosocial effects such as sociability and empathy. Supporting these apparently unique social effects, data from controlled laboratory studies indicate that MDMA alters social feelings, information processing, and behavior in humans, and social behavior in rodents. Here, we review this growing body of evidence. In rodents, MDMA increases passive prosocial behavior (adjacent lying) and social reward while decreasing aggression, effects that may involve serotonin 1A receptor mediated oxytocin release interacting with vasopressin receptor 1A. In humans, MDMA increases plasma oxytocin and produces feelings of social affiliation. It decreases identification of negative facial expressions (cognitive empathy) and blunts responses to social rejection, while enhancing responses to others' positive emotions (emotional empathy) and increasing social approach. Thus, consistent with drug folklore, laboratory administration of MDMA robustly alters social processing in humans and increases social approach in humans and animals. Effects are consistent with increased sociability, with mixed evidence about enhanced empathy. These neurobiologically-complex prosocial effects likely motivate recreational ecstasy use.

Saturday night fever in ecstasy/MDMA dance clubbers: Heightened body temperature and associated psychobiological changes

Aims and rationale: to investigate body temperature and thermal self-ratings of Ecstasy/MDMA users at a Saturday night dance club.

METHODS

68 dance clubbers (mean age 21.6 years, 30 females and 38 males), were assessed at a Saturday night dance club, then 2-3 d later. Three subgroups were compared: 32 current Ecstasy users who had taken Ecstasy/MDMA that evening, 10 abstinent Ecstasy/MDMA users on other psychoactive drugs, and 26 non-user controls (predominantly alcohol drinkers). In a comparatively quiet area of the dance club, each unpaid volunteer had their ear temperature recorded, and completed a questionnaire on thermal feelings and mood states. A similar questionnaire was repeated 2-3 d later by mobile telephone.

RESULTS

Ecstasy/MDMA users had a mean body temperature 1.2°C higher than non-user controls (P < 0.001), and felt significantly hotter and thirstier. The abstinent Ecstasy/MDMA polydrug user group had a mean body temperature intermediate between the other 2 groups, significantly higher than controls, and significantly lower than current Ecstasy/MDMA users. After 2-3 d of recovery, the Ecstasy/MDMA users remained significantly 'thirstier'. Higher body temperature while clubbing was associated with greater Ecstasy/MDMA usage at the club, and younger age of first use. Higher temperature also correlated with lower elation and poor memory 2-3 d later. It also correlated positively with nicotine, and negatively with cannabis.

CONCLUSIONS

Ecstasy/MDMA using dance clubbers had significantly higher body temperature than non-user controls. This heightened body temperature was associated with a number of adverse psychobiological consequences, including poor memory.

Effects of ecstasy on cooperative behaviour and perception of trustworthiness: a naturalistic study

BACKGROUND

Acute recreational use of 3,4-methylenedioxymethamphetamine (MDMA; 'ecstasy') can promote pro-social effects which may alter interpersonal perceptions.

AIMS

To explore such effects, this study investigated whether acute recreational use of ecstasy was associated with changes in individual perception of trustworthiness of people's faces and co-operative behaviours.

METHOD

An independent group, repeated measures design was used in which 17 ecstasy users were tested on the night of drug use (day 0) and again three days later (day 3); 22 controls were tested on parallel days. On each day, participants rated the trustworthiness of 66 faces, carried out three co-operative behaviour tasks (public good; dictator; ultimatum game) and completed mood self-ratings.

RESULTS

Acute ecstasy use was associated with increased face trustworthiness ratings and increased cooperative behaviour on the dictator and ultimatum games; on day 3 there were no group differences on any task. Self-ratings showed the standard acute ecstasy effects (euphoria, energy, jaw clenching) with negative effects (less empathy, compassion, more distrust, hostility) emerging on day 3.

CONCLUSIONS

Our findings of increased perceived trustworthiness and co-operative behaviours following use of ecstasy suggest that a single dose of the drug enhances aspects of empathy. This may in turn contribute to its popularity as a recreational drug and potentially to its enhancement of the therapeutic alliance in psychotherapy.

Effects of MDMA on body temperature in humans

Hyperthermia is a severe complication associated with the recreational use of 3,4-methylenedioxymethamphetamine (MDMA, Ecstasy). In this review, the clinical laboratory studies that tested the effects of MDMA on body temperature are summarized. The mechanisms that underlie the hyperthermic effects of MDMA in humans and treatment of severe hyperthermia are presented. The data show that MDMA produces an acute and dose-dependent rise in core body temperature in healthy subjects. The increase in body temperature is in the range of 0.2-0.8°C and does not result in hyperpyrexia (>40°C) in a controlled laboratory setting. However, moderately hyperthermic body temperatures >38.0°C occur frequently at higher doses, even in the absence of physical activity and at room temperature. MDMA primarily releases serotonin and norepinephrine. Mechanistic clinical studies indicate that the MDMA-induced elevations in body temperature in humans partially depend on the MDMA-induced release of norepinephrine and involve enhanced metabolic heat generation and cutaneous vasoconstriction, resulting in impaired heat dissipation. The mediating role of serotonin is unclear. The management of sympathomimetic toxicity and associated hyperthermia mainly includes sedation with benzodiazepines and intravenous fluid replacement. Severe hyperthermia should primarily be treated with additional cooling and mechanical ventilation.

Effects of 3,4-methylenedioxymethamphetamine (MDMA) and its main metabolites on cardiovascular function in conscious rats

BACKGROUND AND PURPOSE

The cardiovascular effects produced by 3,4-methylenedioxymethamphetamine (MDMA; 'Ecstasy') contribute to its acute toxicity, but the potential role of its metabolites in these cardiovascular effects is not known. Here we examined the effects of MDMA metabolites on cardiovascular function in rats.

EXPERIMENTAL APPROACH

Radiotelemetry was employed to evaluate the effects of s.c. administration of racemic MDMA and its phase I metabolites on BP, heart rate (HR) and locomotor activity in conscious male rats.

KEY RESULTS

MDMA (1-20 mg·kg(-1)) produced dose-related increases in BP, HR and activity. The peak effects on HR occurred at a lower dose than peak effects on BP or activity. The N-demethylated metabolite, 3,4-methylenedioxyamphetamine (MDA), produced effects that mimicked those of MDMA. The metabolite 3,4-dihydroxymethamphetamine (HHMA; 1-10 mg·kg(-1)) increased HR more potently and to a greater extent than MDMA, whereas 3,4-dihydroxyamphetamine (HHA) increased HR, but to a lesser extent than HHMA. Neither dihydroxy metabolite altered motor activity. The metabolites 4-hydroxy-3-methoxymethamphetamine (HMMA) and 4-hydroxy-3-methoxyamphetamine (HMA) did not affect any of the parameters measured. The tachycardia produced by MDMA and HHMA was blocked by the β-adrenoceptor antagonist propranolol.

CONCLUSIONS AND IMPLICATIONS

Our results demonstrate that HHMA may contribute significantly to the cardiovascular effects of MDMA in vivo. As such, determining the molecular mechanism of action of HHMA and the other hydroxyl metabolites of MDMA warrants further study.

Gene expression analysis indicates CB1 receptor upregulation in the hippocampus and neurotoxic effects in the frontal cortex 3 weeks after single-dose MDMA administration in Dark Agouti rats

BACKGROUND

3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") is a widely used recreational drug known to impair cognitive functions on the long-run. Both hippocampal and frontal cortical regions have well established roles in behavior, memory formation and other cognitive tasks and damage of these regions is associated with altered behavior and cognitive functions, impairments frequently described in heavy MDMA users. The aim of this study was to examine the hippocampus, frontal cortex and dorsal raphe of Dark Agouti rats with gene expression arrays (Illumina RatRef bead arrays) looking for possible mechanisms and new candidates contributing to the effects of a single dose of MDMA (15 mg/kg) 3 weeks earlier.

RESULTS

The number of differentially expressed genes in the hippocampus, frontal cortex and the dorsal raphe were 481, 155, and 15, respectively. Gene set enrichment analysis of the microarray data revealed reduced expression of 'memory' and 'cognition', 'dendrite development' and 'regulation of synaptic plasticity' gene sets in the hippocampus, parallel to the upregulation of the CB1 cannabinoid- and Epha4, Epha5, Epha6 ephrin receptors. Downregulated gene sets in the frontal cortex were related to protein synthesis, chromatin organization, transmembrane transport processes, while 'dendrite development', 'regulation of synaptic plasticity' and 'positive regulation of synapse assembly' gene sets were upregulated. Changes in the dorsal raphe region were mild and in most cases not significant.

CONCLUSION

The present data raise the possibility of new synapse formation/synaptic reorganization in the frontal cortex three weeks after a single neurotoxic dose of MDMA. In contrast, a prolonged depression of new neurite formation in the hippocampus is suggested by the data, which underlines the particular vulnerability of this brain region after the drug treatment. Finally, our results also suggest the substantial contribution of CB1 receptor and endocannabinoid mediated pathways in the hippocampal impairments. Taken together the present study provides evidence for the participation of new molecular candidates in the long-term effects of MDMA.

3,4-Methylenedioxymethamphetamine (MDMA) and metabolites disposition in blood and plasma following controlled oral administration

3,4-Methylenedioxymethamphetamine (MDMA) is an illicit phenethylamine ingested for entactogenic and euphoric effects. Although blood is more commonly submitted for forensic analysis, previous human MDMA pharmacokinetics research focused on plasma data; no direct blood-plasma comparisons were drawn. Blood and plasma specimens from 50 healthy adult volunteers (33 males, 17 females, 36 African-American) who ingested recreational 1.0 and 1.6 mg/kg MDMA doses were quantified for MDMA and metabolites 4-hydroxy-3-methoxymethamphetamine (HMMA), 3,4-methylenedioxyamphetamine (MDA), and 4-hydroxy-3-methoxyamphetamine (HMA) by two-dimensional gas chromatography-mass spectrometry. Specimens were collected up to 3 h post-dose and evaluated for maximum concentration (C max), first detection time (t first), time of C max (t max), and 3-h area under the curve (AUC0-3 h); as well as blood metabolite ratios and blood/plasma ratios. Median blood MDMA and MDA C max were significantly greater (p < 0.0005) than in plasma, but HMMA was significantly less (p < 0.0005). HMA was detected in few blood specimens, at low concentrations. Nonlinear pharmacokinetics were not observed for MDMA or MDA in this absorptive phase, but HMMA C max and AUC0-3 h were similar for both doses despite the 1.6-fold dose difference. Blood MDA/MDMA and MDA/HMMA significantly increased (p < 0.0001) over the 3-h time course, and HMMA/MDMA significantly decreased (p < 0.0001). Blood MDMA C max was significantly greater in females (p = 0.010) after the low dose only. Low-dose HMMA AUC0-3 h was significantly decreased in females' blood and plasma (p = 0.027) and in African-Americans' plasma (p = 0.035). These data provide valuable insight into MDMA blood-plasma relationships for forensic interpretation and evidence of sex- and race-based differential metabolism and risk profiles. Figure Median (interquartile range) blood/plasma 3,4-methylenedioxymethamphetamine (MDMA) (a), 4-hydroxy-3-methoxymethamphetamine (HMMA) (b), and 3,4-methylenedioxyamphetamine (MDA) (c) ratios for 3 h after controlled MDMA administration. Changes over time were significant after the 1.6 mg/kg dose for HMMA and MDA (p = 0.013 and p = 0.021), but not for MDMA. No changes over time were significant after the 1.0 mg/kg dose. Note: y-axes do not begin at 0. *p  < 0.05 (low vs. high).

Nonlinear pharmacokinetics of (+/-)3,4-methylenedioxymethamphetamine (MDMA) and its pharmacodynamic consequences in the rat

3,4-Methylenedioxymethamphetamine (MDMA) is a widely abused illicit drug that can cause severe and even fatal adverse effects. However, interest remains for its possible clinical applications in posttraumatic stress disorder and anxiety treatment. Preclinical studies to determine MDMA's safety are needed. We evaluated MDMA's pharmacokinetics and metabolism in male rats receiving 2.5, 5, and 10 mg/kg s.c. MDMA, and the associated pharmacodynamic consequences. Blood was collected via jugular catheter at 0, 0.5, 1, 2, 4, 6, 8, 16, and 24 hours, with simultaneous serotonin (5-HT) behavioral syndrome and core temperature monitoring. Plasma specimens were analyzed for MDMA and the metabolites (±)-3,4-dihydroxymethamphetamine (HHMA), (±)-4-hydroxy-3-methoxymethamphetamine (HMMA), and (±)-3,4-methylenedioxyamphetamine (MDA) by liquid chromatography-tandem mass spectrometry. After 2.5 mg/kg MDMA, mean MDMA Cmax was 164 ± 47.1 ng/ml, HHMA and HMMA were major metabolites, and <20% of MDMA was metabolized to MDA. After 5- and 10-mg/kg doses, MDMA areas under the curve (AUCs) were 3- and 10-fold greater than those after 2.5 mg/kg; HHMA and HMMA AUC values were relatively constant across doses; and MDA AUC values were greater than dose-proportional. Our data provide decisive in vivo evidence that MDMA and MDA display nonlinear accumulation via metabolic autoinhibition in the rat. Importantly, 5-HT syndrome severity correlated with MDMA concentrations (r = 0.8083; P < 0.0001) and core temperature correlated with MDA concentrations (r = 0.7595; P < 0.0001), suggesting that MDMA's behavioral and hyperthermic effects may involve distinct mechanisms. Given key similarities between MDMA pharmacokinetics in rats and humans, data from rats can be useful when provided at clinically relevant doses.

Pharmacological enhancement of exposure-based treatment in PTSD: a qualitative review

There is a good amount of evidence that exposure therapy is an effective treatment for posttraumatic stress disorder (PTSD). Notwithstanding its efficacy, there is room for improvement, since a large proportion of patients does not benefit from treatment. Recently, an interesting new direction in the improvement of exposure therapy efficacy for PTSD emerged. Basic research found evidence of the pharmacological enhancement of the underlying learning and memory processes of exposure therapy. The current review aims to give an overview of clinical studies on pharmacological enhancement of exposure-based treatment for PTSD. The working mechanisms, efficacy studies in PTSD patients, and clinical utility of four different pharmacological enhancers will be discussed: d-cycloserine, MDMA, hydrocortisone, and propranolol.

α₁-Adrenergic receptors contribute to the acute effects of 3,4-methylenedioxymethamphetamine in humans

Preclinical studies implicate a role for α₁-noradrenergic receptors in the effects of psychostimulants, including 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy"). The present study evaluated the effects of the α₁-noradrenergic receptor antagonist doxazosin on the acute pharmacodynamic and pharmacokinetic response to MDMA in 16 healthy subjects. Doxazosin (8 mg/d) or placebo was administered for 3 days before MDMA (125 mg) or placebo using a randomized, double-blind, placebo-controlled, 4-session, crossover design. Doxazosin reduced MDMA-induced elevations in blood pressure, body temperature, and moderately attenuated positive mood but enhanced tachycardia associated with MDMA. The results indicate that α₁-adrenergic receptors contribute to the acute cardiostimulant and to a minor extent possibly also to the thermogenic and euphoric effects of MDMA in humans.

Durability of improvement in post-traumatic stress disorder symptoms and absence of harmful effects or drug dependency after 3,4-methylenedioxymethamphetamine-assisted psychotherapy: a prospective long-term follow-up study

We report follow-up data evaluating the long-term outcomes for the first completed trial of 3,4-methylenedioxymethamphetamine (MDMA)-assisted psychotherapy for chronic, treatment-resistant post-traumatic stress disorder (PTSD) (Mithoefer et al., 2011). All of the 19 subjects who received MDMA-assisted treatment in the original trial participated in the long-term follow-up (LTFU), with 16 out of 19 completing all of the long-term outcome measures, which were administered from 17 to 74 months after the original study's final MDMA session (mean = 45.4; SD = 17.3). Our primary outcome measure used was the Clinician-Administered PTSD Scale (CAPS). Secondary outcome measures were the Impact of Events Scale-Revised (IES-R) and the Neuroticism Extroversion Oppenness Personality Inventory-Revised (NEO PI-R) Personality Inventory. We also collected a long-term follow-up questionnaire. Results for the 16 CAPS completers showed there were no statistical differences between mean CAPS score at LTFU (mean = 23.7; SD = 22.8) (t (matched) = 0.1; df = 15, p = 0.91) and the mean CAPS score previously obtained at Study Exit (mean = 24.6, SD = 18.6). On average, subjects maintained statistically and clinically-significant gains in symptom relief, although two of these subjects did relapse. It was promising that we found the majority of these subjects with previously severe PTSD who were unresponsive to existing treatments had symptomatic relief provided by MDMA-assisted psychotherapy that persisted over time, with no subjects reporting harm from participation in the study.

Carvedilol inhibits the cardiostimulant and thermogenic effects of MDMA in humans

BACKGROUND AND PURPOSE

The use of ± 3,4-methylenedioxymethamphetamine (MDMA, 'ecstasy') is associated with cardiovascular complications and hyperthermia.

EXPERIMENTAL APPROACH

We assessed the effects of the α(1) - and β-adrenoceptor antagonist carvedilol on the cardiostimulant, thermogenic and subjective responses to MDMA in 16 healthy subjects. Carvedilol (50 mg) or placebo was administered 1 h before MDMA (125 mg) or placebo using a randomized, double-blind, placebo-controlled, four-period crossover design. KEY RESULTS Carvedilol reduced MDMA-induced elevations in blood pressure, heart rate and body temperature. Carvedilol did not affect the subjective effects of MDMA including MDMA-induced good drug effects, drug high, drug liking, stimulation or adverse effects. Carvedilol did not alter the plasma exposure to MDMA.

CONCLUSIONS AND IMPLICATIONS

α(1) - and β-Adrenoceptors contribute to the cardiostimulant and thermogenic effects of MDMA in humans but not to its psychotropic effects. Carvedilol could be useful in the treatment of cardiovascular and hyperthermic complications associated with ecstasy use.

Effects of MDMA alone and after pretreatment with reboxetine, duloxetine, clonidine, carvedilol, and doxazosin on pupillary light reflex

RATIONALE

Pupillometry can be used to characterize autonomic drug effects.

OBJECTIVE

This study was conducted to determine the autonomic effects of 3,4-methylenedioxymethamphetamine (MDMA, ecstasy), administered alone and after pretreatment with reboxetine, duloxetine, clonidine, carvedilol, and doxazosin, on pupillary function.

METHODS

Infrared pupillometry was performed in five placebo-controlled randomized studies. Each study included 16 healthy subjects (eight men, eight women) who received placebo-MDMA (125 mg), placebo-placebo, pretreatment-placebo, or pretreatment-MDMA using a crossover design.

RESULTS

MDMA produced mydriasis, prolonged the latency, reduced the response to light, and shortened the recovery time. The impaired reflex response was associated with subjective, cardiostimulant, and hyperthermic drug effects and returned to normal within 6 h after MDMA administration when plasma MDMA levels were still high. Mydriasis was associated with changes in plasma MDMA concentration over time and longer-lasting. Both reboxetine and duloxetine interacted with the effects of MDMA on pupillary function. Clonidine did not significantly reduce the mydriatic effects of MDMA, although it produced miosis when administered alone. Carvedilol and doxazosin did not alter the effects of MDMA on pupillary function.

CONCLUSIONS

The MDMA-induced prolongation of the latency to and reduction of light-induced miosis indicate indirect central parasympathetic inhibition, and the faster recovery time reflects an increased sympathomimetic action. Both norepinephrine and serotonin mediate the effects of MDMA on pupillary function. Although mydriasis is lasting and mirrors the plasma concentration-time curve of MDMA, the impairment in the reaction to light is associated with the subjective and other autonomic effects of MDMA and exhibits acute tolerance.

Duloxetine inhibits effects of MDMA ("ecstasy") in vitro and in humans in a randomized placebo-controlled laboratory study

This study assessed the effects of the serotonin (5-HT) and norepinephrine (NE) transporter inhibitor duloxetine on the effects of 3,4–methylenedioxy­methamphetamine (MDMA, ecstasy) in vitro and in 16 healthy subjects. The clinical study used a double-blind, randomized, placebo-controlled, four-session, crossover design. In vitro, duloxetine blocked the release of both 5-HT and NE by MDMA or by its metabolite 3,4-methylenedioxyamphetamine from transmitter-loaded human cells expressing the 5-HT or NE transporter. In humans, duloxetine inhibited the effects of MDMA including elevations in circulating NE, increases in blood pressure and heart rate, and the subjective drug effects. Duloxetine inhibited the pharmacodynamic response to MDMA despite an increase in duloxetine-associated elevations in plasma MDMA levels. The findings confirm the important role of MDMA-induced 5-HT and NE release in the psychotropic effects of MDMA. Duloxetine may be useful in the treatment of psychostimulant dependence.

Linking the pharmacological content of ecstasy tablets to the subjective experiences of drug users

RATIONALE

Most studies on the subjective effects of ecstasy are based on the assumption that the substance that was taken is 3,4-methylenedioxymethamphetamine (MDMA). However, many tablets sold as ecstasy contain other substances and MDMA in varying doses. So far, few attempts have been made to take this into account while assessing subjective effects.

OBJECTIVES

This study aims to link the pharmacological content of tablets sold as ecstasy to the subjective experiences reported by ecstasy users.

METHODS

Self-reported effects on ecstasy tablets were available from 5,786 drug users who handed in their tablets for chemical analysis at the Drug Information and Monitoring System (DIMS) in the Netherlands. Logistic regression was employed to link the pharmacological content of ecstasy tablets to the self-reported subjective effects and compare effects with MDMA to other substances present.

RESULTS

MDMA showed a strong association with desirable subjective effects, unparalleled by any other psychoactive substance. However, the association of MDMA was dose-dependent, with higher doses (>120 mg/tablet) likely to evoke more adverse effects. The novel psychostimulants mephedrone and p-fluoroamphetamine were considered relatively desirable, whereas meta-chlorophenylpiperazine (mCPP) and p-methoxymethamphetamine (PMMA) were strongly associated with adverse subjective effects. Also, 3,4-methylene-dioxyamphetamine (MDA) and benzylpiperazine (BZP) were not appreciated as replacement for MDMA.

CONCLUSION

Linking the pharmacological content of ecstasy sold on the street to subjective experiences contributes to a better understanding of the wide range of subjective effects ascribed to ecstasy and provides a strong rationale for the prolonged endurance of MDMA as the key ingredient of the ecstasy market.

Memory impairment induced by amphetamine derivatives in laboratory animals and in humans: a review

The 20th century brought with it the so-called club drugs (the most notorious being amphetamine derivatives), which are used by young adults at all-night dance parties. Methamphet­amine and 3,4-methylenedioxymethamphetamine (MDMA or ecstasy) are synthetic drugs with stimulant and psychoactive properties that belong to the amphetamine family. Here, we have reviewed the literature about the cognitive impairment induced by these two amphetamine derivatives and the preclinical and clinical outcomes. Although there is controversial evidence about the effect of methamphetamine and MDMA on learning and memory in laboratory animals, results from published papers demonstrate that amphetamines cause long-term impairment of cognitive functions. A large number of pharmacological receptors have been studied and screened as targets of amphetamine-induced cognitive dysfunction, and extensive research efforts have been invested to provide evidence about the molecular mechanisms behind these cognitive deficits. In humans, there is a considerable body of evidence indicating that methamphetamine and MDMA seriously disrupt memory and learning processes. Although an association between the impairments of memory performance and a history of recreational amphetamine ingestion has also been corroborated, a number of methodological difficulties continue to hamper research in this field, the most important being the concomitant use of other illicit drugs.

MDMA and temperature: a review of the thermal effects of 'Ecstasy' in humans

AIMS

To review the thermal effects of MDMA in humans, and discuss the practical implications.

METHODS

The literature on Ecstasy/MDMA, body temperature, and subjective thermal self-ratings was reviewed, and explanatory models for the changes in thermal homeostasis were examined and debated.

RESULTS

In human placebo-controlled laboratory studies, the effects of MDMA were dose related. Low doses had little effect, moderate doses increased body temperature by around +0.4°C, and higher doses caused a mean increase of +0.7°C. With Ecstasy/MDMA using dance clubbers, the findings showed greater variation, due possibly to uncontrolled factors such as physical activity, ambient temperature, and overcrowding. Some real world studies found average body temperature increases of over +1.0°C. Thermal homeostasis involves a balance between heat production and heat dissipation, and MDMA affects both aspects of this homeostatic equation. Cellular metabolic heat output is increased, and heat dissipation mechanisms are stressed, with the onset of sweating delayed. Subjective responses of 'feeling hot' or 'hot-cold flushes' are frequent, but can show individual variation. Some recreational users report that heat increases or reinstates the positive mood effects of Ecstasy/MDMA. The dangers of acute hyperthermia can include rare fatalities. It is unclear why moderate hyperthermia can occasionally progress to severe hyperpyrexia, although it may reflect a combination or cascade of events. In chronic terms, the bioenergetic stress model notes that the adverse psychobiological effects of MDMA are heightened by various co-stimulatory factors, including heat stress.

CONCLUSIONS

MDMA increases core body temperature and thermal stress in humans.

Blood pressure and heart rate effects, weight loss and maintenance during long-term phentermine pharmacotherapy for obesity

There is a perception that phentermine pharmacotherapy for obesity increases blood pressure and heart rate (HR), exposing treated patients to increased cardiovascular risk. We collected data from phentermine-treated (PT) and phentermine-untreated (P0) patients at a private weight management practice, to examine blood pressure, HR, and weight changes. Records of 300 sequential returning patients were selected who had been treated with a low-carbohydrate ketogenic diet if their records included complete weight, blood pressure, and HR data from seven office examinations during the first 12 weeks of therapy. The mean time in therapy, time range, and mode was 92 (97.0), 12-624, and 52 weeks. 14% were normotensive, 52% were prehypertensive, and 34% were hypertensive at their first visit or had a previous diagnosis of hypertension. PT subjects systolic blood pressure/diastolic blood pressure (SBP/DBP) declined from baseline at all data points (SBP/DBP -6.9/-5.0 mm Hg at 26, and -7.3/-5.4 at 52 weeks). P0 subjects' declines of SBP/DBP at both 26 and 52 weeks were -8.9/-6.3 but the difference from the treated cohort was not significant. HR changes in treated/untreated subjects at weeks 26 (-0.9/-3.5) and 52 (+1.2/-3.6) were not significant. Weight loss was significantly greater in the PT cohort for week 1 through 104 (P = 0.0144). These data suggest phentermine treatment for obesity does not result in increased SBP, DBP, or HR, and that weight loss assisted with phentermine treatment is associated with favorable shifts in categorical blood pressure and retardation of progression to hypertension in obese patients.

Effects of the α₂-adrenergic agonist clonidine on the pharmacodynamics and pharmacokinetics of 3,4-methylenedioxymethamphetamine in healthy volunteers

The mechanism of action of 3,4-methylenedioxymethamphetamine (MDMA; ecstasy) involves the carrier-mediated and potentially vesicular release of monoamines. We assessed the effects of the sympatholytic α₂-adrenergic receptor agonist clonidine (150 μg p.o.), which inhibits the neuronal vesicular release of norepinephrine, on the cardiovascular and psychotropic response to MDMA (125 mg p.o.) in 16 healthy subjects. The study used a randomized, double-blind, placebo-controlled crossover design with four experimental sessions. The administration of clonidine 1 h before MDMA reduced the MDMA-induced increases in plasma norepinephrine concentrations and blood pressure but only to the extent that clonidine lowered norepinephrine levels and blood pressure compared with placebo. Thus, no interaction was found between the cardiovascular effects of the two drugs. Clonidine did not affect the psychotropic effects or pharmacokinetics of MDMA. The lack of an interaction of the effects of clonidine and MDMA indicates that vesicular release of norepinephrine, which is inhibited by clonidine, does not critically contribute to the effects of MDMA in humans. Although clonidine may be used in the treatment of stimulant-induced hypertensive reactions, the present findings do not support a role for α₂-adrenergic receptor agonists in the prevention of psychostimulant dependence.

Methylenedioxymethamphetamine (MDMA, 'Ecstasy'): Neurodegeneration versus Neuromodulation

The amphetamine analogue 3,4-methylenedioxymethamphetamine (MDMA, ‘ecstasy’) is widely abused as a recreational drug due to its unique psychological effects. Of interest, MDMA causes long-lasting deficits in neurochemical and histological markers of the serotonergic neurons in the brain of different animal species. Such deficits include the decline in the activity of tryptophan hydroxylase in parallel with the loss of 5-HT and its main metabolite 5-hydoxyindoleacetic acid (5-HIAA) along with a lower binding of specific ligands to the 5-HT transporters (SERT). Of concern, reduced 5-HIAA levels in the CSF and SERT density have also been reported in human ecstasy users, what has been interpreted to reflect the loss of serotonergic fibers and terminals. The neurotoxic potential of MDMA has been questioned in recent years based on studies that failed to show the loss of the SERT protein by western blot or the lack of reactive astrogliosis after MDMA exposure. In addition, MDMA produces a long-lasting down-regulation of SERT gene expression; which, on the whole, has been used to invoke neuromodulatory mechanisms as an explanation to MDMA-induced 5-HT deficits. While decreased protein levels do not necessarily reflect neurodegeneration, the opposite is also true, that is, neuroregulatory mechanisms do not preclude the existence of 5-HT terminal degeneration.

Pill content, dose and resulting plasma concentrations of 3,4-methylendioxymethamphetamine (MDMA) in recreational 'ecstasy' users

AIMS

To improve our understanding of the pharmacology of 'ecstasy' in recreational environments; in particular, to describe the composition of ecstasy pills, patterns of ecstasy use and the relationship between dose of 3,4-methylendioxymethamphetamine (MDMA) and resulting plasma concentrations.

DESIGN, SETTING AND PARTICIPANTS

A naturalistic observational study of 56 experienced 'ecstasy' users in recreational settings in Australia.

MEASUREMENTS

Drug use patterns (number of pills consumed, other drugs consumed). drug content of pills and resultant plasma concentrations of MDMA and related drugs were assessed by gas chromatography/mass spectrometry (GC/MS).

FINDINGS

Ecstasy pills generally contained MDMA, but this was often combined with other drugs such as 3,4-ethylendioxyethylamphetamine (MDEA) and methamphetamine. The dose of MDMA per pill ranged from 0 to 245 mg and users consumed from one-half to five pills, with the total dose consumed ranging up to 280 mg. Plasma concentrations of MDMA increased with number of pills consumed and cumulative MDMA dose. Use of larger numbers of pills was associated with extended exposure to the drug.

CONCLUSIONS

MDMA is the major active drug in ecstasy pills, but there is a high degree of variation in doses. Use of multiple pills over the course of one session is common and results in a sustained increase in MDMA plasma concentrations over a number of hours. This is likely to lead to a much greater exposure of the brain to MDMA than would be predicted from controlled single-dose pharmacokinetic studies.

The norepinephrine transporter inhibitor reboxetine reduces stimulant effects of MDMA ("ecstasy") in humans

This study assessed the pharmacodynamic and pharmacokinetic effects of the interaction between the selective norepinephrine (NE) transporter inhibitor reboxetine and 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") in 16 healthy subjects. The study used a double-blind, placebo-controlled crossover design. Reboxetine reduced the effects of MDMA including elevations in plasma levels of NE, increases in blood pressure and heart rate, subjective drug high, stimulation, and emotional excitation. These effects were evident despite an increase in the concentrations of MDMA and its active metabolite 3,4-methylenedioxyamphetamine (MDA) in plasma. The results demonstrate that transporter-mediated NE release has a critical role in the cardiovascular and stimulant-like effects of MDMA in humans.

MDMA and methamphetamine: some paradoxical negative and positive mood changes in an acute dose laboratory study

RATIONALE

This study investigated the acute mood effects of oral MDMA, methamphetamine, and placebo in a double-blind laboratory study.

METHODS

Fifty-two healthy participants comprised abstinent recreational users of stimulant drugs, 27 female and 25 male, mean age 24.8 years. Three test sessions involved acute 100 mg oral 3.4-methylendioxymethamphetamine (MDMA), 0.42 mg/kg oral methamphetamine, and matching placebo. Drug administration was counterbalanced, testing was double-blind, and medical supervision was present throughout. Car-driving performance on a laboratory simulator was assessed after 3 and 24 h, with the findings being presented elsewhere. Positive and negative moods (PANAS self-ratings) were completed before drug administration, 3, 4.5, and 24 h later. Blood samples were taken to monitor drug plasma levels.

RESULTS

Following MDMA, there were no significant increases in positive moods, whereas negative moods were significantly higher than under placebo. Methamphetamine led to significant increases in both positive and negative moods. The MDMA findings contrast with the elated moods, typically noted by dance clubbers on Ecstasy. However, they are consistent with some previous laboratory findings, since a wide array of positive and negative mood changes have been demonstrated. One possible explanatory factor was the neutral environmental situation, particularly if a primary action of MDMA is to intensify ongoing psychological states. Other explanatory factors, such as dosage, gender, post-drug timing, neurohormonal aspects, and social factors, are also discussed.

CONCLUSIONS

In the laboratory, acute methamphetamine led to significantly higher positive moods. However, against expectations, MDMA did not generate a significant increase in positive moods.

Metabolism and disposition of 3,4-methylenedioxymethamphetamine ("ecstasy") in baboons after oral administration: comparison with humans reveals marked differences

The baboon is potentially an attractive animal for modeling 3,4-methylenedioxymethamphetamine (MDMA) effects in humans. Baboons self-administer MDMA, are susceptible to MDMA neurotoxicity, and are suitable for positron emission tomography, the method most often used to probe for MDMA neurotoxicity in humans. Because pharmacokinetic equivalence is a key feature of a good predictive animal model, we compared the pharmacokinetics of MDMA in baboons and humans. Baboons were trained to orally consume MDMA. Then, pharmacokinetic profiles of MDMA and its major metabolites were determined after various oral MDMA doses using the same analytical method recently used to perform similar studies in humans. Results indicate that MDMA pharmacokinetics after oral ingestion differ markedly between baboons and humans. Baboons had little or no MDMA in their plasma but had high plasma concentrations of 3,4-dihydroxymethamphetamine (HHMA), pointing to much more extensive first-pass metabolism of MDMA in baboons than in humans. Other less prominent differences included less O-methylation of HHMA to 4-hydroxy-3-methoxymethamphetamine, greater N-demethylation of MDMA to 3,4-methylenedioxyamphetamine, and a shorter half-life of HHMA in the baboon. To our knowledge, this is the first study to characterize MDMA metabolism and disposition in the baboon. Differences in MDMA pharmacokinetics between baboons and humans suggest that the baboon may not be ideal for modeling human MDMA exposure. However, the unusually rapid conversion of MDMA to HHMA in the baboon may render this animal uniquely useful for clarifying the relative role of the parent compound (MDMA) versus metabolites (particularly HHMA) in the biological actions of MDMA.

MDMA ("ecstasy") abuse as an example of dopamine neuroplasticity

A number of reviews have focused on the short- and long-term effects of MDMA and, in particular, on the persistent deficits in serotonin neurotransmission that accompany some exposure regimens. The mechanisms underlying the serotonin deficits and their relevance to various behavioral and cognitive consequences of MDMA use are still being debated. It has become clear, however, that some individuals develop compulsive and uncontrolled drug-taking that is consistent with abuse. For other drugs of abuse, this transition has been attributed to neuroadaptations in central dopamine mechanisms that occur as a function of repeated drug exposure. A question remains as to whether similar neuroadaptations occur as a function of exposure to MDMA and the impact of serotonin neurotoxicity in the transition from use to abuse. This review focuses specifically on this issue by first providing an overview of human studies and then reviewing the animal literature with specific emphasis on paradigms that measure subjective effects of drugs and self-administration as indices of abuse liability. It is suggested that serotonin deficits resulting from repeated exposure to MDMA self-administration lead to a sensitized dopaminergic response to the drug and that this sensitized response renders MDMA comparable to other drugs of abuse.

Is ecstasy an "empathogen"? Effects of ±3,4-methylenedioxymethamphetamine on prosocial feelings and identification of emotional states in others

BACKGROUND

Users of ±3,4-methylenedioxymethamphetamine (MDMA), "ecstasy," report that the drug produces unusual psychological effects, including increased empathy and prosocial feelings. These "empathogenic" effects are cited as reasons for recreational ecstasy use and also form the basis for the proposed use of MDMA in psychotherapy. However, they have yet to be characterized in controlled studies. Here, we investigate effects of MDMA on an important social cognitive capacity, the identification of emotional expression in others, and on socially relevant mood states.

METHODS

Over four sessions, healthy ecstasy-using volunteers (n = 21) received MDMA (.75, 1.5 mg/kg), methamphetamine (METH) (20 mg), and placebo under double-blind, randomized conditions. They completed self-report ratings of relevant affective states and undertook tasks in which they identified emotions from images of faces, pictures of eyes, and vocal cues.

RESULTS

MDMA (1.5 mg/kg) significantly increased ratings of feeling "loving" and "friendly", and MDMA (.75 mg/kg) increased "loneliness". Both MDMA (1.5 mg/kg) and METH increased "playfulness"; only METH increased "sociability". MDMA (1.5 mg/kg) robustly decreased accuracy of facial fear recognition relative to placebo.

CONCLUSIONS

The drug MDMA increased "empathogenic" feelings but reduced accurate identification of threat-related facial emotional signals in others, findings consistent with increased social approach behavior rather than empathy. This effect of MDMA on social cognition has implications for both recreational and therapeutic use. In recreational users, acute drug effects might alter social risk-taking while intoxicated. Socioemotional processing alterations such as those documented here might underlie possible psychotherapeutic benefits of this drug; further investigation of such mechanisms could inform treatment design to maximize active components of MDMA-assisted psychotherapy.

A psychobiological rationale for oxytocin in the treatment of posttraumatic stress disorder

Although cognitive-behavioral therapy (CBT) is an effective treatment for posttraumatic stress disorder (PTSD), many patients fail to attain remission with CBT. The authors propose augmentation of CBT with oxytocin in the treatment of PTSD. Oxytocin has a combination of pharmacologic effects that result in a "sense of safety" for the patient, which is a prerequisite to successful treatment of PTSD. We suggest a dual explanatory mechanism as to why oxytocin may be effective: through a reduction of fear response (decreasing amygdala activation, inhibiting fear response, and enhancing extinction learning) and through an increase of social interaction (activating social reward-related brain regions increasing engagement in the therapeutic alliance). Given that PTSD is marked by deficits in anxiety/stress regulation and in social functioning, and that oxytocin is implicated in both of these areas, oxytocin seems a likely candidate for treatment of patients with PTSD. Further clinical studies of the therapeutic value of oxytocin are indicated.

Effects of MDMA on sociability and neural response to social threat and social reward

RATIONALE

+/-3,4-Methylenedioxymethamphetamine (MDMA, "ecstasy") reportedly produces unique subjective effects, including increased sociability, feelings of closeness with others, and reduced interpersonal defensiveness. Despite their apparent importance in recreational and potential psychotherapeutic use of MDMA, the defining characteristics and neurobiological mechanisms of these interpersonal effects are poorly understood.

MATERIALS AND METHODS

We investigated acute effects of MDMA on self-reported sociability and neuronal activation in response to socially threatening (angry and fearful faces) and socially rewarding (happy faces) stimuli. Assessment of social threat response focused on amygdala activation, whereas assessment of social reward focused on ventral striatum activation. Healthy volunteers (N = 9) reporting past ecstasy use completed three experimental sessions, receiving MDMA (0.75 and 1.5 mg/kg) and placebo (PBO) under double-blind conditions. During peak drug effects, participants underwent functional magnetic resonance imaging while viewing standardized images depicting emotional facial expressions including angry, fearful, happy, and neutral expressions. They also completed standardized self-report measures of sociability.

RESULTS

MDMA (1.5 mg/kg) increased self-reported sociability compared to MDMA (0.75 mg/kg) and PBO. MDMA (1.5 mg/kg) attenuated left amygdala response to angry facial expressions compared to PBO, but MDMA did not affect amygdala reactivity to fearful expressions. MDMA (0.75 mg/kg) enhanced ventral striatum response to happy expressions relative to PBO.

CONCLUSIONS

These data present the first evidence that MDMA may increase sociability in humans both by diminishing responses to threatening stimuli and enhancing responses to rewarding social signals.

Effects of dose and route of administration on pharmacokinetics of (+ or -)-3,4-methylenedioxymethamphetamine in the rat

Based on animal data, there is speculation that (+ or -)-3,4-methylenedioxymethamphetamine (MDMA) is neurotoxic to humans. Extrapolation of MDMA findings from animals to humans requires assessment of pharmacokinetics in various species, and low-dose administration data from rats are lacking. In this study, we examine MDMA pharmacokinetics in rats given low (2 mg/kg) and high (10 mg/kg) doses of racemic MDMA via intraperitoneal, subcutaneous, and oral routes. Repeated blood specimens were collected from venous catheters, and plasma was assayed for MDMA and its metabolites, 4-hydroxy-3-methoxymethamphetamine (HMMA) and 3,4-methylenedioxyamphetamine (MDA), by gas chromatography-mass spectrometry. After 2 mg/kg, maximum MDMA concentrations (C(max)) were approximately 200 ng/ml for intraperitoneal and subcutaneous routes, but less for the oral route. MDMA plasma half-lives were <1 h for low-dose groups, whereas HMMA and MDA half-lives were >2 h. After 10 mg/kg, MDMA areas under the curve (AUCs) were 21-fold (intraperitoneal), 10-fold (subcutaneous), and 36-fold (oral) greater than those at 2 mg/kg. In contrast, HMMA AUC values in high-dose groups were <3-fold above those at 2 mg/kg. Several new findings emerge from this report of low-dose MDMA pharmacokinetics in rats. First, 2 mg/kg MDMA in rats can produce MDMA C(max) values similar to those in humans, perhaps explaining why both species discriminate 1.5 mg/kg MDMA in laboratory paradigms. Second, our data provide additional support for nonlinear kinetics of MDMA in rats, and, analogous to humans, this phenomenon appears to involve impaired drug metabolism. Finally, given key similarities between MDMA pharmacokinetics in rats and humans, data from rats may be clinically relevant when appropriate dosing conditions are used.

How could MDMA (ecstasy) help anxiety disorders? A neurobiological rationale

Exposure therapy is known to be an effective treatment for anxiety disorders. Nevertheless, exposure is not used as much as it should be, and instead patients are often given supportive medications such as serotonin reuptake inhibitors (SSRIs) and benzodiazepines, which may even interfere with the extinction learning that is the aim of treatment. Given that randomized controlled trials are now investigating a few doses of +/-3,4-methylenedioxymethamphetamine (MDMA, 'ecstasy') in combination with psychotherapy for treatment-resistant anxiety disorders, we would like to suggest the following three mechanisms for this potentially important new approach: 1) MDMA increases oxytocin levels, which may strengthen the therapeutic alliance; 2) MDMA increases ventromedial prefrontal activity and decreases amygdala activity, which may improve emotional regulation and decrease avoidance and 3) MDMA increases norepinephrine release and circulating cortisol levels, which may facilitate emotional engagement and enhance extinction of learned fear associations. Thus, MDMA has a combination of pharmacological effects that, in a therapeutic setting, could provide a balance of activating emotions while feeling safe and in control, as described in case reports of MDMA-augmented psychotherapy. Further clinical and preclinical studies of the therapeutic value of MDMA are indicated.