Stimulant effects of 3,4-methylenedioxymethamphetamine (MDMA) 75 mg and methylphenidate 20 mg on actual driving during intoxication and withdrawal

Safety and cognitive pharmacodynamics following dose escalations with 3-methylmethcathinone (3-MMC): a first in human, designer drug study

3-Methylmethcathinone (3-MMC) is a designer drug that belongs to the group of synthetic cathinones. The compound has been scheduled in many jurisdictions because of public health concerns associated with excessive use. To date, there are no clinical studies that have evaluated the risk profile of 3-MMC in the recreational range of low to moderate doses. The current, first-in-human study (N = 14) assessed the impact of three escalating doses of 3-MMC (25, 50 and 100 mg) on vital signs, neurocognitive function, state of consciousness, appetite and drug desire, in a cross-over, placebo-controlled trial. A battery of neurocognitive tests and questionnaires as well as measures of vital signs were repeatedly administered up to 5 h after dosing. Overall, 3-MMC caused dose-dependent increases in heart rate and blood pressure, though not of clinical significance, and feelings of subjective high. Additionally, 3-MMC induced dose-related enhancement of task performance across several neurocognitive domains, including processing speed, cognitive flexibility, psychomotor function, attention and memory. Impulse control was not affected by 3-MMC. Participants also reported mild increases in dissociative and psychedelic effects, decreased appetite, and gave greater ratings of liking and wanting for 3-MMC that were transient over time. Overall, the cardiovascular, psychostimulant and psychotomimetic profile of 3-MMC appears consistent with that of compounds structurally related to amphetamine. It is concluded that low to moderate doses of 3-MMC were well tolerated and safe and that potential health risks might only occur at high or excessive doses of 3-MMC.

Driving performance and ocular activity following acute administration of 10 mg methylphenidate: A randomised, double-blind, placebo-controlled study

BACKGROUND

Methylphenidate is a routinely prescribed treatment for attention-deficit/hyperactivity disorder with misuse potential owing to its perceived performance-enhancing and euphoric properties. Although clinically effective, there is limited understanding of how methylphenidate affects safety-sensitive tasks such as driving when used by healthy individuals.

AIM

Explore the acute effects of 10 mg methylphenidate on driving performance and gaze behaviour.

METHODS

Twenty-five fully licensed, healthy adults (mean age = 33.5 ± 7.8 years, 64% male) took part in two 40-min simulated highway drives with simultaneous eye movements monitored using a proprietary automotive-grade driver monitoring system (Seeing Machines). Driving performance was assessed using the standard deviation of lateral position, standard deviation of speed and steering variability. Visual scanning efficiency was determined using ocular metrics, such as fixation duration and rate, gaze transition entropy, and stationary gaze entropy, were assessed to determine visual scanning efficiency.

RESULTS

Methylphenidate significantly improved driving performance by reducing lane weaving and speed variation, particularly in the latter half of the drive. Although a significant reduction in fixation duration was observed, all other ocular metrics remained unchanged.

CONCLUSIONS

Methylphenidate mitigates performance decrements typically associated with prolonged and monotonous driving. The absence of pronounced oculomotor effects suggests that a single 10 mg dose of methylphenidate has no deleterious impact on visual scanning behaviour during driving tasks with low-to-moderate cognitive demand. Future research should investigate the effects of methylphenidate under various dosing and driving conditions to better understand its impact.

TRIAL REGISTRATION

ACTRN12620000499987.

Driving under the influence of cocaine and MDMA: Relationship between blood concentrations and results from clinical test of impairment

The general use of cocaine is increasing in recent years, while the trend for 3,4-methylenedioxymethamphetamine (MDMA) is less clear. The relationship between blood concentrations and impairment is poorly understood, which complicates interpretation. The aims of this study were to report prevalence and blood concentrations of cocaine and MDMA in drugged drivers, and to investigate the relationship between blood concentrations and impairment. Samples of whole blood were collected from apprehended drivers in the period 2000-2022, and a clinical test of impairment (CTI) was simultaneously performed. The samples were initially analyzed for cocaine and MDMA using gas chromatography-mass spectrometry (until 2009 and 2012, respectively), and later using ultra-high-performance liquid chromatography-tandem mass spectrometry. Overall, cocaine was detected in 2,331 cases and MDMA in 2,569 cases. There were 377 and 85 mono cases of cocaine and MDMA, respectively. In the mono cases, the median cocaine concentration was 0.09 mg/L (range: 0.02-1.15 mg/L), and 54% of the drivers were clinically impaired. The median MDMA concentration was 0.19 mg/L (range: 0.04-1.36 mg/L), and 38% were clinically impaired. There was a statistically significant difference in the median cocaine concentration between drivers assessed as not impaired (0.07 mg/L) and drivers assessed as impaired (0.10 mg/L) (P = 0.009). There was also a significant effect of the blood concentration of cocaine (adjusted odds ratio [aOR] = 6.42, 95% confidence interval [CI] = 1.13-36.53, P = 0.036) and driving during the evening/night-time (aOR = 2.17, 95% CI = 1.34-3.51, P = 0.002) on the probability of being assessed as impaired on the CTI. No significant differences were found for MDMA. Many drivers are not assessed as impaired on a CTI following cocaine or especially MDMA use. For cocaine, a relationship between blood concentrations and impairment was demonstrated, but this could not be shown for MDMA.

Convergent validity of video-based observer rating of drowsiness, against subjective, behavioral, and physiological measures

Driver drowsiness is a widely recognized cause of motor vehicle accidents. Therefore, a reduction in drowsy driving crashes is required. Many studies evaluating the crash risk of drowsy driving and developing drowsiness detection systems, have used observer rating of drowsiness (ORD) as a reference standard (i.e. ground truth) of drowsiness. ORD is a method of human raters evaluating the levels of driver drowsiness, by visually observing a driver. Despite the widespread use of ORD, concerns remain regarding its convergent validity, which is supported by the relationship between ORD and other drowsiness measures. The objective of the present study was to validate video-based ORD, by examining correlations between ORD levels and other drowsiness measures. Seventeen participants performed eight sessions of a simulated driving task, verbally responding to Karolinska sleepiness scale (KSS), while infra-red face video, lateral position of the participant's car, eye closure, electrooculography (EOG), and electroencephalography (EEG) were recorded. Three experienced raters evaluated the ORD levels by observing facial videos. The results showed significant positive correlations between the ORD levels and all other drowsiness measures (i.e., KSS, standard deviation of the lateral position of the car, percentage of time occupied by slow eye movement calculated from EOG, EEG alpha power, and EEG theta power). The results support the convergent validity of video-based ORD as a measure of driver drowsiness. This suggests that ORD might be suitable as a ground truth for drowsiness.

Effects of solriamfetol on on-the-road driving performance in participants with excessive daytime sleepiness associated with obstructive sleep apnoea

OBJECTIVE

To evaluate the impact of solriamfetol, a dopamine and norepinephrine reuptake inhibitor, on on-the-road driving in participants with excessive daytime sleepiness (EDS) associated with obstructive sleep apnoea (OSA).

METHODS

Eligible participants were aged 21-75 years with OSA and EDS (Maintenance of Wakefulness Test mean sleep latency <30 minutes and Epworth Sleepiness Scale score ≥10). Participants were randomised 1:1 to solriamfetol (150 mg/day [3 days], then 300 mg/day [4 days]) or placebo for 7 days, before crossover to the other treatment paradigm. On Day 7 of each period, standardised on-road driving tests occurred (2 and 6 hours postdose). Standard deviation of lateral position (SDLP) was the primary endpoint.

RESULTS

Solriamfetol significantly reduced SDLP at 2 (n = 34; least squares mean difference, -1.1 cm; 95% CI, -1.85, -0.32; p = 0.006) and 6 hours postdose (n = 32; least squares mean difference, -0.8 cm; 95% CI, -1.58, -0.03; p = 0.043). Two hours postdose, 4 placebo-treated and 1 solriamfetol-treated participants had incomplete driving tests; 6 hours postdose, 7 and 3 participants, respectively, had incomplete tests. Common treatment-emergent adverse events included headache, nausea, and insomnia.

CONCLUSIONS

Solriamfetol 300 mg/day significantly improved on-the-road driving performance in participants with EDS associated with OSA.

Remembering Molly: Immediate and delayed false memory formation after acute MDMA exposure

The entactogen 3,4-Methylenedioxymethamphetamine (MDMA) is increasingly being recognized for its therapeutic potential but is also widespread in nightlife settings where it may co-occur with crime. Since previous research detected impaired verbal memory during acute MDMA intoxication, understanding the drug's ramifications in an applied legal context becomes crucial. We conducted a double-blind, placebo-controlled trial to examine acute and delayed effects of MDMA (75 mg) on false memory in 60 healthy volunteers with a history of MDMA use, using three well-established false memory methods: a basic, associative word list (Deese/Roediger-McDermott (DRM)) paradigm and two applied misinformation tasks using a virtual reality crime. Memory was tested immediately (encoding and retrieval under drug influence) and 1 week later (retrieval when sober). Small MDMA-induced impairments of true memory in the word list task were detected at both time points. MDMA increased false memory for related but non-critical lures during the immediate test, and decreased false memory for critical lures after a delay. Episodic memory assessed in the misinformation tasks was not consistently affected. Findings indicate a complex memory profile but no heightened vulnerability to external suggestion in response to MDMA intoxication. Recommendations for future applied legal psychological research include adding measures of recall on top of recognition, using study designs that separate the different memory phases, and potentially testing higher doses. Further research on false memories and suggestibility using imagination procedures can also be relevant for the clinical context.

The prevalence of alcohol and other drugs in fatal road crashes in Victoria, Australia

BACKGROUND

Driving under the influence of drugs, including alcohol, is a globally recognised risk factor for road traffic crashes. While the prevalence of alcohol and other drugs in fatal road crashes has been examined in other countries, recent data investigating drug driving in fatal Australian crashes are limited. This study aimed to examine how the presence of alcohol and other drugs in fatal road trauma in Victoria has changed over time in different road users.

METHODS

A population-based review of road trauma deaths was performed over the period of 01 July 2006 to 30 June 2016 in Victoria, Australia, using data from the National Coronial Information System (NCIS) and the Victorian State Trauma Registry (VSTR). Drugs were grouped according to type and analysed accordingly. Poisson regression models were used to determine change in incidence rates over the study period.

RESULTS

There were 2287 road traffic fatalities with complete toxicology data (97% of all road traffic fatalities). Alcohol (blood alcohol concentration, BAC) was the most commonly detected drug (>0.001 g/100 mL: 21.1%; >0.05 g/100 mL: 18.4%), followed by opioids (17.3%), THC (13.1%), antidepressants (9.7%), benzodiazepines (8.8%), amphetamine-type stimulants (7.1%), ketamine (3.4%), antipsychotics (0.9%) and cocaine (0.2%). Trends demonstrated changing use over time with specific drugs. Alcohol positive road fatalities declined 9% per year in passenger car/4WD drivers (IRR = 0.91, 95% CI: 0.88-0.95). The incidence of strong opioids (oxycodone, fentanyl, morphine, and methadone) increased 6% per year (IRR = 1.06; 95% CI: 1.02-1.10). Methylamphetamine was detected in 6.6% of cases and showed a yearly increase of 7% (IRR = 1.07; 95% CI: 1.01-1.13). The incidence of THC remained unchanged over the period, observed in 13.1% of cases. Stronger opioids were more commonly detected among pedal cyclists (19.0%) and pedestrians (20.9%) while THC was more commonly detected among motorcyclists (19.8%) and other light vehicle drivers (17.6%).

CONCLUSIONS

A decline in the prevalence of alcohol in fatalities suggests that law enforcement and public health strategies in Australia to address road fatalities and drink-driving may have had a positive effect. However, increases were observed in the incidence of other potentially impairing drugs including opioids and amphetamines, specifically methylamphetamine, indicating a concerning trend in road safety in Victoria that warrants further monitoring.

Of mice and men on MDMA: A translational comparison of the neuropsychobiological effects of 3,4-methylenedioxymethamphetamine ('Ecstasy')

MDMA (3,4-methylendioxymethamphetamine), also known as Ecstasy, is a stimulant drug recreationally used by young adults usually in dance clubs and raves. Acute MDMA administration increases serotonin, dopamine and noradrenaline by reversing the action of the monoamine transporters. In this work, we review the studies carried out over the last 30 years on the neuropsychobiological effects of MDMA in humans and mice and summarise the current knowledge. The two species differ with respect to the neurochemical consequences of chronic MDMA, since it preferentially induces serotonergic dysfunction in humans and dopaminergic neurotoxicity in mice. However, MDMA alters brain structure and function and induces hormonal, psychomotor, neurocognitive, psychosocial and psychiatric outcomes in both species, as well as physically damaging and teratogen effects. Pharmacological and genetic studies in mice have increased our knowledge of the neurochemical substrate of the multiple effects of MDMA. Future work in this area may contribute to developing pharmacological treatments for MDMA-related disorders.

3,4-Methylenedioxymethamphetamine-assisted psychotherapy for treatment of chronic posttraumatic stress disorder: A randomized phase 2 controlled trial

BACKGROUND

Posttraumatic stress disorder often does not resolve after conventional psychotherapies or pharmacotherapies. Pilot studies have reported that 3,4-methylenedioxymethamphetamine (MDMA) combined with psychotherapy reduces posttraumatic stress disorder symptoms.

AIMS

This pilot dose response trial assessed efficacy and safety of MDMA-assisted psychotherapy across multiple therapy teams.

METHODS

Twenty-eight people with chronic posttraumatic stress disorder were randomized in a double-blind dose response comparison of two active doses (100 and 125 mg) with a low dose (40 mg) of MDMA administered during eight-hour psychotherapy sessions. Change in the Clinician-Administered PTSD Scale total scores one month after two sessions of MDMA served as the primary outcome. Active dose groups had one additional open-label session; the low dose group crossed over for three open-label active dose sessions. A 12-month follow-up assessment occurred after the final MDMA session.

RESULTS

In the intent-to-treat set, the active groups had the largest reduction in Clinician-Administered PTSD Scale total scores at the primary endpoint, with mean (standard deviation) changes of -26.3 (29.5) for 125 mg, -24.4 (24.2) for 100 mg, and -11.5 (21.2) for 40 mg, though statistical significance was reached only in the per protocol set ( p=0.03). Posttraumatic stress disorder symptoms remained lower than baseline at 12-month follow-up ( p<0.001) with 76% ( n=25) not meeting posttraumatic stress disorder criteria. There were no drug-related serious adverse events, and the treatment was well-tolerated.

CONCLUSIONS

Our findings support previous investigations of MDMA-assisted psychotherapy as an innovative, efficacious treatment for posttraumatic stress disorder.

Safety Profile and Neurocognitive Function Following Acute 4-Fluoroamphetamine (4-FA) Administration in Humans

Availability of novel psychoactive substances (NPS) exponentially increased over the last years. Risk evaluations of NPS are hampered by the lack of pharmacological studies in humans on health parameters. The aim of the present study was to evaluate safety and neurocognitive function of healthy volunteers (N = 12) who received single doses of 100 and 150 mg 4-fluoroamphetamine (4-FA), a phenethylamine that has been associated with severe cardiovascular and cerebrovascular complications. The study was set-up as a placebo controlled, within subject, phase 1 trial as it was the first to administer 4-FA to humans under controlled conditions. Overall, 4-FA produced a strong elevation in blood pressure up until 4–5 h after administration that was followed by a sustained increase in heart rate. After an interim review of safety data from five participants, a decision was taken to cancel administration of 150 mg. We subsequently obtained complete datasets for placebo and 100 mg 4-FA treatments only. Effects of 4-FA on mood and neurocognitive function were most distinct at 1 h post drug and included significant elevations of vigor, friendliness, elation, arousal, positive mood, as well as improvements in attention and motor performance. Negative affect was also reported as time progressed in the acute phase and even more so during the subacute phase. Overall, the influence of 4-FA on vital signs, mood, and neurocognition was similar to that observed with other stimulants. Present findings confirm clinical observations of acute toxicity among 4-FA users and warrant warnings about potential health risks associated with 4-FA use.

No major role of norepinephrine transporter gene variations in the cardiostimulant effects of MDMA

PURPOSE

Methylenedioxymethamphetamine (MDMA, ecstasy) is used recreationally and frequently leads to sympathomimetic toxicity. MDMA produces cardiovascular and subjective stimulant effects that were shown to partially depend on the norepinephrine transporter (NET)-mediated release of norepinephrine and stimulation of α1-adrenergic receptors. Genetic variants, such as single-nucleotide polymorphisms (SNPs), of the NET gene (SLC6A2) may explain interindividual differences in the acute stimulant-type responses to MDMA in humans.

METHODS

We characterized the effects of common genetic variants of the SLC6A2 gene (rs168924, rs47958, rs1861647, rs2242446, and rs36029) on cardiovascular and subjective stimulation after MDMA administration in 124 healthy subjects in a pooled analysis of eight double-blind, placebo-controlled studies.

RESULTS

Carriers of the GG genotype of the SLC6A2 rs1861647 SNP presented higher elevations of heart rate and rate-pressure product after MDMA than subjects with one or no G alleles. Subjects with a C allele in the SLC6A2 rs2242446 SNP presented higher elevations of the heart rate after MDMA administration compared with the TT genotype. Subjects with the AA genotype of the SLC6A2 rs36029 SNP presented higher elevations of mean arterial pressure and rate pressure product after MDMA administration than carriers of the G allele. The SLC6A2 rs168924 and rs47958 SNPs did not alter the response to MDMA.

CONCLUSIONS

Genetic polymorphisms of the SLC6A2 gene weakly moderated the acute cardiovascular response to MDMA in controlled studies and may play a minor role in adverse cardiovascular events when MDMA is used recreationally.

Conversion factors for assessment of driving impairment after exposure to multiple benzodiazepines/z-hypnotics or opioids

AIMS

Norway has introduced legal concentration limits in blood for 28 non-alcohol drugs in driving under the influence cases. As of 2016 this legislation also regulates the assessment of combined effects of multiple benzodiazepines and opioids. We herein describe the employed methodology for the equivalence tables for concentrations of benzodiazepines/z-hypnotics and opioids implemented in the Norwegian Road Traffic Act.

METHODS

Legislative limits corresponding to impairment at blood alcohol concentrations (BAC) of 0.02%, 0.05% and 0.12% were established for 15 different benzodiazepines and opioids. This was based on a concept of a linear relationship between blood drug concentration and impairment in drug naïve users. Concentration ratios between these drugs were used to establish conversion factors and calculate net impairment using diazepam and morphine equivalents.

RESULTS

Conversion factors were established for 14 benzodiazepines/z-hypnotics (alprazolam, bromazepam, clobazam, clonazepam, etizolam, flunitrazepam, lorazepam, nitrazepam, nordiazepam, oxazepam, phenazepam, temazepam, zolpidem and zopiclone) and two opioids (methadone and oxycodone).

CONCLUSIONS

Conversion factors to calculate diazepam and morphine equivalents for benzodiazepines/z-hypnotics and selected opioids, respectively, have been operative in the Norwegian Road Traffic Act as of February 2016. Calculated equivalents can be applied by the courts to meter out sanctions.

Nonmedical use of prescription drugs in the European Union

BACKGROUND

Nonmedical prescription drug use (NMPDU) refers to the self-treatment of a medical condition using medication without a prescriber's authorization as well as use to achieve euphoric states. This article reports data from a cross-national investigation of NMPDU in five European Countries, with the aim to understand the prevalence and characteristics of those engaging in NMPDU across the EU.

METHODS

A parallel series of self-administered, cross-sectional, general population surveys were conducted in 2014. Data were collected using multi-stage quota sampling and then weighted using General Exponential Model. A total of 22,070 non-institutionalized participants, aged 12 to 49 years, in 5 countries: Denmark, Germany, Great Britain, Spain, and Sweden. Lifetime and past-year nonmedical use of prescription medications such as stimulants, opioids, and sedatives were ascertained via a modified version of the World Health Organization's Composite International Diagnostic Interview. Information about how the medications were acquired for NMPDU were also collected from the respondent.

RESULTS

Lifetime and past-year prevalence of nonmedical prescription drug use was estimated for opioids (13.5 and 5.0 %), sedatives (10.9 and 5.8 %), and stimulants (7.0 and 2.8 %). Germany exhibited the lowest levels of NMPDU, with Great Britain, Spain, and Sweden having the highest levels. Mental and sexual health risk factors were associated with an increased likelihood of past-year nonmedical prescription drug use. Among past-year users, about 32, 28, and 52 % of opioid, sedative, and stimulant nonmedical users, respectively, also consumed illicit drugs. Social sources (sharing by friends/family) were the most commonly endorsed methods of acquisition, ranging from 44 % (opioids) to 62 % (sedatives). Of interest is that Internet pharmacies were a common source of medications for opioids (4.1 %), stimulants (7.6 %), and sedatives (2.7 %).

CONCLUSIONS

Nonmedical prescription drug use was reported across the five EU countries we studied, with opioids and sedatives being the most prevalent classes of prescription psychotherapeutics. International collaborations are needed for continued monitoring and intervention efforts to target population subgroups at greatest risk for NMDU.

Amphetamine-type stimulant use and the risk of injury or death as a result of a road-traffic accident: A systematic review of observational studies

Amphetamine-type substances are frequently detected among drivers injured or killed due to road-trauma. However, the role of this substance in crash causation remains equivocal. We performed a systematic review to evaluate existing evidence regarding the association between amphetamine use and the risk of injury or death due to road traffic accidents. A bibliographical search of PubMed, SafetyLit, Scopus, and Science Direct literature databases from 01 January 1980 until May 2015 was performed. The quality of included studies was assessed using the Newcastle-Ottowa Scale (NOS) (cut-off of ≥7 indicated high quality). Inter-rater reliability between three independent reviewers for the NOS was calculated using Cohens kappa (κ) statistic, and best-evidence synthesis was performed. A total of 182 articles were found. Nine studies met eligibility criteria for inclusion for review, and seven studies were included for best-evidence synthesis. Best-evidence synthesis demonstrated a conflicting level of evidence for associations between the use of-amphetamine-type substances and the risk of sustaining an injury, and a moderate level of evidence between amphetamine use and the risk of death due to road trauma. This is the first review to synthesise evidence regarding the association between amphetamine-type substance use and the risk of injury or death due to a road traffic accident. More conclusive evidence of death due to road trauma among amphetamine users may reflect significant and global deficits in functioning associated with effective vehicular control under the influence of this substance. Additional high quality, sufficiently powered studies are required to elucidate the magnitude of these associations.

On-the-road driving performance the morning after bedtime use of suvorexant 15 and 30 mg in healthy elderly

RATIONALE

Suvorexant is a first-in-class orexin receptor antagonist for treating insomnia. There is a general concern that hypnotics may impair next-morning driving ability.

OBJECTIVE

The objective of this study was to evaluate next-morning driving performance in older adults after single and repeated doses of suvorexant.

METHODS

Double-blind, randomized, placebo-controlled, 4-period crossover study in 24 healthy volunteers (10 females), aged 65-80 years. Subjects were treated with suvorexant (15 and 30 mg) for eight consecutive nights, zopiclone 7.5 mg nightly on days 1 and 8, and placebo. Driving performance was assessed on days 2 and 9 (9 h after dosing) using a 1-h standardized highway driving test in normal traffic, measuring standard deviation of lateral position (SDLP). Drug-placebo differences in SDLP >2.4 cm were considered to reflect clinically meaningful driving impairment.

RESULTS

Driving performance as measured by SDLP was not impaired following suvorexant. Mean drug-placebo differences in SDLP following suvorexant 15 and 30 mg on day 2 and 9 were 0.6 cm or less. Their 90 % CIs were all below the threshold of 2.4 cm for clinical relevance and included zero, indicating effects were not clinically meaningful or statistically significant. Symmetry analysis showed no significant differences between the number of participants who had SDLP differences >2.4 cm and those who had SDLP differences <-2.4 cm following suvorexant.

CONCLUSIONS

There was no clinically meaningful residual effect of suvorexant 15 and 30 mg on next-morning driving (9 h after bedtime dosing) in healthy older adults, as assessed by mean changes in SDLP and by the number of participants on drug versus placebo that exceeded a predetermined threshold for clinically meaningful impairment.

Cannabis effects on driving lateral control with and without alcohol

BACKGROUND

Effects of cannabis, the most commonly encountered non-alcohol drug in driving under the influence cases, are heavily debated. We aim to determine how blood Δ(9)-tetrahydrocannabinol (THC) concentrations relate to driving impairment, with and without alcohol.

METHODS

Current occasional (≥1×/last 3 months, ≤3days/week) cannabis smokers drank placebo or low-dose alcohol, and inhaled 500mg placebo, low (2.9%)-THC, or high (6.7%)-THC vaporized cannabis over 10min ad libitum in separate sessions (within-subject design, 6 conditions). Participants drove (National Advanced Driving Simulator, University of Iowa) simulated drives (∼0.8h duration). Blood, oral fluid (OF), and breath alcohol samples were collected before (0.17h, 0.42h) and after (1.4h, 2.3h) driving that occurred 0.5-1.3h after inhalation. We evaluated standard deviations of lateral position (lane weave, SDLP) and steering angle, lane departures/min, and maximum lateral acceleration.

RESULTS

In N=18 completers (13 men, ages 21-37years), cannabis and alcohol increased SDLP. Blood THC concentrations of 8.2 and 13.1μg/L during driving increased SDLP similar to 0.05 and 0.08g/210L breath alcohol concentrations, the most common legal alcohol limits. Cannabis-alcohol SDLP effects were additive rather than synergistic, with 5μg/L THC+0.05g/210L alcohol showing similar SDLP to 0.08g/210L alcohol alone. Only alcohol increased lateral acceleration and the less-sensitive lane departures/min parameters. OF effectively documented cannabis exposure, although with greater THC concentration variability than paired blood samples.

CONCLUSIONS

SDLP was a sensitive cannabis-related lateral control impairment measure. During drive blood THC ≥8.2μg/L increased SDLP similar to notably-impairing alcohol concentrations. Despite OF's screening value, OF variability poses challenges in concentration-based effects interpretation.

Why all stimulant drugs are damaging to recreational users: an empirical overview and psychobiological explanation

AIMS

Stimulant drugs such as nicotine and Ecstasy/3, 4-methylenedioxymethamphetamine (MDMA) are taken for positive reasons, yet their regular use leads to deficits rather than gains. This article outlines the psychobiological rationale for this paradox.

METHODS

The empirical literature on nicotine, cocaine, amphetamine, Ecstasy/MDMA, and mephedrone are reviewed. A theoretical explanation for why they are problematic to humans is then described.

RESULTS

The acute effects of central nervous system (CNS) stimulants are typically positive, with greater alertness and emotional intensity. However, in the post-drug recovery period, the opposite feelings develop, with lethargy and low moods. All recreational stimulants cause mood fluctuation, although it is most pronounced in drugs with rapid onset and comedown (e.g. nicotine and cocaine), explaining why they are the most addictive. Parallel fluctuations occur across many psychological and neurocognitive functions, with users suffering various off-drug deficits. CNS stimulants also affect the hypothalamic-pituitary-adrenal axis, impairing sleep, disrupting homeostasis, and exacerbating psychiatric distress. Neuroimaging studies reveal altered brain activity patterns in regular users. These problems are related to lifetime usage but commence in novice users.

CONCLUSIONS

Repetitive CNS stimulation is potentially damaging to the organism, both acutely and chronically. The review describes the various psychobiological systems through which recreational stimulant drugs impair human well-being.

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).

Driving on ice: impaired driving skills in current methamphetamine users

RATIONALE

Previous research indicates a complex link between methamphetamine (METH) and driving performance. Acute dosing with amphetamines has improved driving-related performance in some laboratory studies, while epidemiological studies suggest an association between METH use, impaired driving, and accident culpability.

METHODS

Current METH users were compared to a control group of nonusers on driving simulator performance. Groups were matched for age, gender, and driving experience. Subjects were assessed for current drug use, drug dependence, and drug levels in saliva/blood as well as personality variables, sleepiness, and driving performance.

RESULTS

METH users, most of whom met the criteria for METH dependence, were significantly more likely to speed and to weave from side to side when driving. They also left less distance between their vehicle and oncoming vehicles when making a right-hand turn. This risky driving was not associated with current blood levels of METH or its principal metabolite, amphetamine, which varied widely within the METH group. Other drugs were detected (principally low levels of THC or MDMA) in some METH users, but at levels that were unlikely to impair driving performance. There were higher levels of impulsivity and antisocial personality disorder in the METH-using cohort.

CONCLUSIONS

These findings confirm indications from epidemiological studies of an association between METH use and impaired driving ability and provide a platform for future research to further explore the factors contributing to increased accident risk in this population.

The prevalence and nature of stopped on-the-road driving tests and the relationship with objective performance impairment

INTRODUCTION AND OBJECTIVES

The on-the-road driving test in normal traffic is applied to examine the impact of drugs on driving performance. Although participants are accompanied by a licensed driving instructor, under Dutch law, the driver is primarily responsible for safe driving and is not permitted to continue driving when it is judged that the drug compromises safety. This review examined the prevalence and nature of stopped driving tests, and the relationship with Standard Deviation of Lateral Position (SDLP), i.e. the "weaving of the car".

MATERIALS AND METHODS

A literature search was conducted to gather all publications on clinical trials that applied the on-the-road driving test, examining the effects of Central Nervous System (CNS)-drugs such as anxiolytics, antidepressants, antihistamines, analgesics, and hypnotics.

RESULTS

47 papers reported on 50 Dutch clinical trials in which 1059 subjects participated (903 healthy volunteers and 156 patients). A total of 7232 driving tests were performed; 5050 after drug treatment and 2042 after placebo. 3.1% of all driving tests were terminated before completion: 4.1% after drug treatment, and 0.7% after placebo. The decision to stop a driving test was 3-4 times more often made by the driving instructor than the subject. The most common reasons for stopping were the driver feeling tired or sleepy, or the driving instructor noticing signs of drowsiness and performance impairment. Although SDLP values of stopped driving tests are sometimes high, there is no clear relationship between SDLP (changes from placebo) and the decision to stop a driving test. Based on 8 studies that reported exact data, 39.6% of stopped drivers had a lower and 60.4% had a higher SDLP than 35 cm, i.e. the cut-off point of safe driving. This confirms that perception of the driver as well as judgment by the instructor of driving to be 'unsafe' differs between individuals.

CONCLUSION

Driving tests are sometimes stopped after drug treatment or placebo. The decision to stop driving is not a good correlate of objective performance.

The acute effects of 3,4-methylenedioxymethamphetamine and methamphetamine on driving: a simulator study

OBJECTIVES

Illicit drugs such as MDMA and methamphetamine are commonly abused drugs that have also been observed to be prevalent in drivers injured in road accidents. Their exact effect on driving and driving behavior has yet to be thoroughly investigated.

METHODS

Sixty-one abstinent recreational users of illicit drugs comprised the participant sample, with 33 females and 28 males, mean age 25.45 years. The three testing sessions involved oral consumption of 100 mg MDMA, 0.42 mg/kg methamphetamine, or a matching placebo. The drug administration was counter-balanced, double-blind, and medically supervised. At each session driving performance was assessed 3 h and 24 h post drug administration on a computerized driving simulator.

RESULTS

At peak concentration overall impairment scores for driving (F(2,118)=9.042, p<0.001) and signaling (F(2,118)=4.060, p=0.020) were significantly different for the daytime simulations. Performance in the MDMA condition was worse than both the methamphetamine (p=0.023) and placebo (p<0.001) conditions and the methamphetamine condition was also observed to be worse in comparison to the placebo (p=0.055). For signaling adherence, poorer signaling adherence occurred in both the methamphetamine (p=0.006) and MDMA (p=0.017) conditions in comparison to placebo in the daytime simulations.

CONCLUSIONS

The findings of this study have for the first time illustrated how both MDMA and methamphetamine effect driving performance, and provide support for legislation regarding testing for the presence of illicit drugs in impaired or injured drivers as deterrents for driving under the influence of illicit drugs.

Driving under the influence of amphetamine-like drugs

Scientific opinions differ whether the use of stimulants causes deterioration in driving skills. In 1857 of 8709 cases of driving under the influence of drugs, amphetamine-like drugs (amphetamine, methamphetamine, and methylendioxyamphetamine) were present either alone or together with other licit or illicit drugs. In 338 cases, amphetamines were the only psychoactive substance group in plasma at mean, median, and highest concentrations of 0.18, 0.12, and 1.05 mg/L, respectively. A widespread opinion is that after the consumption of amphetamines, centrally stimulating effects with corresponding consequences on safe driving are expected. In contrast, many cases were observed that rather suggested an influence of centrally sedating substances when considering the psycho-physical conditions. Relations between concentration and effect could not be established. The apparent sedation is probably the consequence of sleep deprivation during an amphetamine binge and the after-effects of the drug.

The effect of d,l-methamphetamine on simulated driving performance

RATIONALE

Illicit drugs such as methamphetamine are commonly abused drugs that have also been observed to be prevalent in drivers injured in road accidents. The exact effect of methamphetamine or its specific isomers on driving and driving behaviour have yet to be thoroughly investigated.

METHODS

Twenty healthy recreational illicit stimulant users (ten males, ten females), aged between 21 and 34 years (mean = 24.3 years, SD = 3.4 years), attended two testing sessions involving oral consumption of 0.42 mg/kg d,l-methamphetamine or a matching placebo. The drug administration was counterbalanced, double-blind, and medically supervised. At each session, driving performance was assessed 2.5 h post-drug administration.

RESULTS

Mean blood and saliva d,l-methamphetamine concentrations of approximately 90 and 400 ng/ml, respectively, at 2 h and 95 and 475 ng/ml at 3 h were observed. These levels of d,l-methamphetamine were found not to significantly impair, or improve, driving performance at the 2.5-h post-drug administration time point.

CONCLUSIONS

The findings of this study illustrate that d,l-methamphetamine has no significant effect on simulated driving performance.

Effects of dexamphetamine with and without alcohol on simulated driving

RATIONALE

In party circuits dexamphetamine is frequently used in combination with alcohol. It is hypothesized that co-administration of dexamphetamine to alcohol might reduce the sedative effects of alcohol, but may potentiate risk-taking behaviour.

OBJECTIVES

The study was aimed at assessing the effects of alcohol, dexamphetamine and the combination of both on simulated driving and cognitive performance.

METHOD

Eighteen subjects participated in a randomized, crossover, placebo-controlled study employing four conditions: 10 mg dexamphetamine, 0.8 g/kg alcohol, 10 mg dexamphetamine + 0.8 g/kg alcohol, and placebo. Fundamental driving skills and risk-taking behaviour were assessed in a driving simulator. Subjects also completed vigilance and divided attention tasks, and subjective ratings.

RESULTS

Mean BAC levels during simulated driving were between 0.91‰ and 0.64‰. Subjects using alcohol showed a significantly larger mean standard deviation of lateral position and shorter accepted gap time and distance. Use of alcohol or dexamphetamine + alcohol was associated with a higher frequency of red light running and collisions than the dexamphetamine or placebo conditions. Performance of vigilance and divided attention tasks was significantly impaired in the alcohol condition and, to a lesser degree, in the dexamphetamine + alcohol condition.

CONCLUSION

Single doses of 0.8 g/kg alcohol increased risk-taking behaviours and impaired tracking, attention and reaction time during a 3-h period after drinking when BACs declined from 0.9 to 0.2 mg/ml. The stimulatory effects of co-administration of dexamphetamine 10 mg were not sufficient to overcome the impairing effects of alcohol on skills related to driving.

MDMA (ecstasy) effects on actual driving performance before and after sleep deprivation, as function of dose and concentration in blood and oral fluid

RATIONALE

Experimental research has shown that 3,4-methylenedioxymethamphetamine (MDMA) can improve some psychomotor driving skills when administered during the day. In real life, however, MDMA is taken during the night, and driving may likely occur early in the morning after a night of "raving" and sleep loss.

OBJECTIVES

The present study assessed the effects of MDMA on road-tracking and car-following performance in on-the-road driving tests in normal traffic.

METHODS

Sixteen recreational MDMA users participated in a randomized double-blind placebo-controlled four-way cross-over design. They received single, evening doses of 0, 25, 50, and 100 mg MDMA on separate occasions. Actual driving tests were conducted in the evening when MDMA serum concentrations were maximal and in the morning after a night of sleep loss.

RESULTS

The primary measure of driving, i.e., standard deviation of lateral position (SDLP, a measure of weaving) was significantly increased during driving tests in the morning in all treatment conditions, irrespective of MDMA dose and concentration. The increments in SDLP were of high clinical relevance and comparable to those observed for alcohol at blood alcohol concentrations >0.8 mg/mL. These impairments were primarily caused by sleep loss.

CONCLUSIONS

In general, MDMA did not affect driving performance nor did it change the impairing effects of sleep loss. It is concluded that MDMA cannot compensate for the impairing effects of sleep loss and that drivers who are under the influence of MDMA and sleep deprived are unfit to drive.

Effects of alcohol (BAC 0.5‰) and ecstasy (MDMA 100 mg) on simulated driving performance and traffic safety

RATIONAL

An increasing number of fatal road-accidents have been reported in which ecstasy was found in the blood of drivers. Although, ecstasy is frequently found to have been used in combination with alcohol, studies on the acute effects of ecstasy co-administered with alcohol on driving performance are relatively rare.

OBJECTIVE

The present study was designed to establish the extent of driver impairment as a consequence of ecstasy or combined ecstasy and alcohol use as compared to driving under the influence of 0.3‰, 0.5‰ and 0.8‰ alcohol. Furthermore, subjective performance was also assessed.

RESULTS

Alcohol and ecstasy mainly influenced automated driving performance such as lateral and speed control. However, small to no effects of the substances were found on more complex driving behaviour. Overall, variance within the different driving measures was high especially when participants were treated with 3.4-methylenedioxy-methamphetamine (MDMA) and alcohol. Furthermore, equivalence testing showed that combined use may lead to impaired driving for some, but not all, drivers. Participants rated their own performance to be slightly worse than normal in both studies. Since driving was actually seriously deteriorated, this was a falsely positive assessment of their condition.

CONCLUSIONS

The dissociation between subjective perceptions and objective performance decrements are important notions for traffic safety since this may affect a driver's judgement of whether or not it is safe to drive. For example, an intoxicated individual might decide to drive because the feelings of alertness caused by MDMA cloud the impairing effects of other drugs such as alcohol, thereby creating a potentially serious risk for traffic safety.

Risky car following in abstinent users of MDMA

Ecstasy (MDMA) use raises concerns because of its association with risky driving. We evaluated driving performance and risk taking in abstinent recreational MDMA users in a simulated car following task that required continuous attention and vigilance. Drivers were asked to follow two car lengths behind a lead vehicle (LV). Three sinusoids generated unpredictable LV velocity changes. Drivers could mitigate risk by following further behind the erratic LV. From vehicle trajectory data we performed a Fourier analysis to derive measures of coherence, gain, and delay. These measures and headway distance were compared between the different groups. All MDMA drivers met coherence criteria indicating cooperation in the car following task. They matched periodic changes in LV velocity similar to controls (abstinent THC users, abstinent alcohol users, and non-drug users), militating against worse vigilance. While all participants traveled approximately 55 mph (89 kph), the MDMA drivers followed 64 m closer to the LV and demonstrated 1.04 s shorter delays to LV velocity changes than other driver groups. The simulated car following task safely discriminated between driving behavior in abstinent MDMA users and controls. Abstinent MDMA users do not perform worse than controls, but may assume extra risk. The control theory framework used in this study revealed behaviors that might not otherwise be evident.

A European study on alcohol and drug use among young drivers: the TEND by Night study design and methodology

Background

Young individuals are the age group with the highest risk of car accidents. One of main explanations relies on the use of psychoactive substances (alcohol, illegal and medicinal drugs), which are known to be major risk factors of road accidents, and whose consumption is almost universally more common among younger drivers. Although the correlation between psychoactive substances use and decrease in driving performance has been established in controlled experimental or laboratory settings, few studies were conducted in naturalistic circumstances. The TEND by Night project has been designed to evaluate the relationship between driving performance and psychoactive substances assumption in young drivers enrolled at typical places of consumption.

Methods/Design

The TEND by Night project, endorsed by the European Commission, is a multidisciplinary, multi-centric, cross-sectional study conducted in six European countries (Italy, Belgium/Netherlands, Bulgaria, Spain, Poland and Latvia). The study population consists of 5000 young drivers aged 16-34 years, attending recreational sites during weekend nights. The intervention is based on the portal survey technique and includes several steps at the entrance and exit of selected sites, including the administration of semi-structured questionnaires, breath alcohol test, several drug assumption test, and measurement of the reaction time using a driving simulator. The main outcome is the difference in reaction time between the entrance and exit of the recreation site, and its correlation with psychoactive substances use. As a secondary outcome it will be explored the relationship between reaction time difference and the amount of consumption of each substance. All analyses will be multivariate.

Discussion

The project methodology should provide some relevant advantages over traditional survey systems. The main strengths of the study include the large and multicentric sample, the objective measurement of substance assumption (which is typically self-reported), the application of a portal survey technique and the simultaneous evaluation of several psychoactive substances.

Dose-related effects of MDMA on psychomotor function and mood before, during, and after a night of sleep loss

INTRODUCTION

3,4-methylenedioxymethamphetamine (MDMA) is known to improve psychomotor function and mood when measured during daytime. However, MDMA users tend to take this drug at dance parties while staying awake for prolonged periods of time.

SUBJECTS AND METHODS

This study was designed to assess dose-related residual effects of MDMA on psychomotor function and mood after a night without sleep. Sixteen recreational MDMA users received single doses of 25, 50, and 100 mg MDMA in a randomized, double-blind, placebo-controlled cross-over study.

RESULTS

Results showed that sleep loss significantly impaired psychomotor function. MDMA generally did not affect performance but did improve rapid information processing at the highest dose in the morning after administration. In the evening, MDMA also increased subjective ratings of positive mood at every dose and subjective arousal at the highest dose. These subjective effects were no longer present after a night of sleep loss.

DISCUSSION

It is concluded that sleep deprivation impairs psychomotor function and that stimulant effects of MDMA are not sufficient to compensate for this impairment.

Psychoactive medication and traffic safety

Driving a car is important to maintain independence and participate in society. Many of those who use psychoactive medication are outpatients and are thus likely to drive a vehicle. Most common adverse effects that impair driving are reduced alertness, affected psychomotor functioning and impaired vision. This review discusses the effects on driving ability of most commonly prescribed psychoactive drugs, including hypnotics, antidepressants, antihistamines, analgesics and stimulant drugs. Within these categories of medicines significant differences concerning their impact on driving ability are evident. The International Council on Alcohol, Drugs and Traffic Safety (ICADTS) categorization can help physicians to make a choice between treatments when patients want to drive a car.

Factors associated with driving under the influence of alcohol and drugs among an Australian sample of regular ecstasy users

The aim of the present study was to investigate factors associated with driving under the influence (DUI) of alcohol and other drugs (ecstasy, cannabis and methamphetamine) among a group of regular ecstasy users. Participants were those who participated in the Australian Ecstasy and related Drug Reporting System (EDRS) in 2007 and had recently driven a motor vehicle (n=573). Participants were administered a semi-structured face-to-face interview which included questions about ecstasy and other drug use, associated health-related issues, and risk behaviours. Close to half of those who were current consumers of ecstasy, cannabis, and methamphetamine had recently driven under the influence of these drugs, while two-fifths of current alcohol users reported recent drink driving. Frequency of use for each substance was the most significant correlate of DUI of alcohol, cannabis, and methamphetamine, suggesting that interventions targeting high frequency and problematic drug use may be useful in reducing the occurrence of DUI for these substances. Low perception of the likelihood of having an accident was the most significant correlate of DUI of ecstasy and also related significantly to DUI of other substances. Perceptions of low likelihood of being apprehended by police and demographic characteristics such as younger age and male sex were also weakly associated with DUI. Together these findings have important implications for targeted interventions aimed at reducing the occurrence of DUI among regular drug users.

Substance-involved driving: predicting driving after using alcohol, marijuana, and other drugs

OBJECTIVES

Substantial research has examined the influence of alcohol, marijuana, and other illicit drugs on driving performance; however, which psychosocial characteristics of individuals who drive while under the influence of alcohol (DUIA), marijuana (DUIM), and other drugs (DUID), how these characteristics interrelate with each other, and how they differ across degrees of substance-involved driving (SID) have not been thoroughly investigated. This article identified psychosocial predictors of SID while accounting for driving behavior and the type and level of substance use and examined the associations of psychosocial characteristics and SID with citations for traffic offenses.

METHODS

Telephone survey data and state driver history records for a sample of 5,244 young adults were analyzed using t-tests and logistic and multinomial logistic regression analysis to examine the correlates and predictors of substance-involved driving.

RESULTS

Psychosocial characteristics predicted DUIA, DUIM, and DUID when tested in separate models and adjusting for driving behavior. When the substance in question was added to each model, a unique association between psychosocial characteristics and DUIA remained, but the associations between psychosocial characteristics and DUIM and DUID were completely mediated by the frequency of marijuana use and level of other drug use in their respective models. Multinomial logistic regression predicting the degree of SID, which was based on the types and combinations of SID behaviors, showed that after controlling for the use of alcohol, marijuana, and other drugs, psychosocial characteristics maintained a unique association with the degree of SID. Finally, when adjusting for driving behavior and psychosocial characteristics, the degree of SID predicted having a traffic offense.

CONCLUSIONS

These results indicate that reducing substance use is not the only means of targeting substance-involved driving. Interventions could have enhanced effectiveness if they also targeted individual psychosocial and behavioral characteristics, either to alter these behaviors or by tailoring the intervention or program for these characteristics.

Methylphenidate significantly improves driving performance of adults with attention-deficit hyperactivity disorder: a randomized crossover trial

Although patients with attention-deficit hyperactivity disorder (ADHD) have reported improved driving performance on methylphenidate, limited evidence exists to support an effect of treatment on driving performance and some regions prohibit driving on methylphenidate. A randomized, crossover trial examining the effects of methylphenidate versus placebo on highway driving in 18 adults with ADHD was carried out. After three days of no treatment, patients received either their usual methylphenidate dose (mean: 14.7 mg; range: 10-30 mg) or placebo and then the opposite treatment after a six to seven days washout period. Patients performed a 100 km driving test during normal traffic, 1.5 h after treatment administration. Standard deviation of lateral position (SDLP), the weaving of the car, was the primary outcome measure. Secondary outcome measurements included the standard deviation of speed and patient reports of driving performance. Driving performance was significantly better in the methylphenidate than in the placebo condition, as reflected by the SDLP difference (2.3 cm, 95% CI = 0.8-3.8, P = 0.004). Variation in speed was similar on treatment and on placebo (-0.05 km/h, 95% CI = -0.4 to 0.2, P = 0.70). Among adults with ADHD, with a history of a positive clinical response to methylphenidate, methylphenidate significantly improves driving performance.

Acute neuropsychological effects of MDMA and ethanol (co-)administration in healthy volunteers

RATIONALE

In Western societies, a considerable percentage of young people expose themselves to 3,4-methylenedioxymethamphetamine (MDMA or "ecstasy"). Commonly, ecstasy is used in combination with other substances, in particular alcohol (ethanol). MDMA induces both arousing as well as hallucinogenic effects, whereas ethanol is a general central nervous system depressant.

OBJECTIVE

The aim of the present study is to assess the acute effects of single and co-administration of MDMA and ethanol on executive, memory, psychomotor, visuomotor, visuospatial and attention function, as well as on subjective experience.

MATERIALS AND METHODS

We performed a four-way, double-blind, randomised, crossover, placebo-controlled study in 16 healthy volunteers (nine male, seven female) between the ages of 18-29. MDMA was given orally (100 mg) and blood alcohol concentration was maintained at 0.6 per thousand by an ethanol infusion regime.

RESULTS

Co-administration of MDMA and ethanol was well tolerated and did not show greater impairment of performance compared to the single-drug conditions. Impaired memory function was consistently observed after all drug conditions, whereas impairment of psychomotor function and attention was less consistent across drug conditions.

CONCLUSIONS

Co-administration of MDMA and ethanol did not exacerbate the effects of either drug alone. Although the impairment of performance by all drug conditions was relatively moderate, all induced significant impairment of cognitive function.

Acute effects of nocturnal doses of MDMA on measures of impulsivity and psychomotor performance throughout the night

INTRODUCTION

Previous studies on the acute effects of MDMA on psychomotor performance and impulsivity showed that MDMA acts as a stimulant. These studies assessed performance during daytime, whereas in real life, dance-attendees leaving a party use the drug during the night.

OBJECTIVES

The present study aimed to assess the effects of nocturnal doses of MDMA on psychomotor performance and impulsivity during the night and after a night of sleep deprivation.

MATERIALS AND METHODS

Fourteen healthy subjects participated in a double-blind, placebo-controlled, two-way within-subject study. The treatment was MDMA (75 and 50 mg) divided over the evening or double placebo. Psychomotor and impulsivity tasks were conducted four times throughout the evening and night. A vigilance test was conducted once, at 5 A.M.,: and a sleepiness scale was presented to the subjects ten times throughout the evening and night.

RESULTS

MDMA impaired tracking performance in a simple tracking task. Divided attention task performance was also impaired as indicated by a decrease in secondary task performance under the influence of MDMA compared with placebo. MDMA did not affect impulsivity measures. Vigilance performance decreased as a function of time on task, but this decrement was less during MDMA treatment compared to placebo. After the administration of MDMA, the sleepiness scale scores were lower during the night when compared with placebo. This difference between MDMA and placebo disappeared in the morning.

CONCLUSION

It is concluded that nocturnal doses of MDMA may produce impairments of tracking performance and divided attention throughout the night that are additive to performance impairment produced by sleep loss.

MDMA and alcohol effects, combined and alone, on objective and subjective measures of actual driving performance and psychomotor function

RATIONALE

The party drug ecstasy is frequently used in combination with other drugs like marihuana and alcohol. In addition, a substantial proportion of the MDMA users has claimed to drive a car when under the influence of MDMA and/or other drugs.

OBJECTIVE

To assess the effects of MDMA and alcohol, combined and alone, on actual driving performance and laboratory tasks related to driving.

METHODS

Eighteen healthy subjects participated in a double-blind, placebo-controlled, six-way cross-over study. Treatments consisted of MDMA 0, 75, and 100 mg with and without alcohol, aiming at 0.06 mg/ml BAC. Laboratory tests (critical tracking task, object movement estimation task) were conducted between 1.5 and 2 h postdrug (0.5 and 1 h postalcohol). Actual driving tests (road tracking test, car-following test) were conducted between 3 and 5 h postdrug (2 and 4 h postalcohol). Subjects completed the addiction research center inventory (ARCI) and rated their driving quality and mental effort during driving.

RESULTS

Alcohol alone impaired critical tracking performance, as well as a number of actual driving performance parameters [i.e., standard deviation of lateral position (SDLP), brake reaction time, and coherence]. MDMA alone reduced SDLP and standard deviation of speed. MDMA significantly moderated alcohol induced impairment of road tracking performance but did not affect alcohol impairments of car-following and laboratory task performance. Subjective data seemed to support objective data.

CONCLUSION

MDMA moderated the impairing effects of a low dose of alcohol on road tracking performance but it could not overcome alcohol-induced impairment on other aspects of driving behavior or driving related performance.