Caroline T. J. Lamers

Plasma, oral fluid and sweat wipe ecstasy concentrations in controlled and real life conditions

In a double-blind placebo controlled study on psychomotor skills important for car driving (Study 1), a 75 mg dose of +/- 3,4-methylenedioxymethamphetamine (MDMA) was administered orally to 12 healthy volunteers who were known to be recreational MDMA-users. Toxicokinetic data were gathered by analysis of blood, urine, oral fluid and sweat wipes collected during the first 5h after administration. Resultant plasma concentrations varied from 21 to 295 ng/ml, with an average peak concentration of 178 ng/ml observed between 2 and 4h after administration. MDA concentrations never exceeded 20 ng/ml. Corresponding MDMA concentrations in oral fluid, as measured with a specific LC-MS/MS method (which required only 50 microl of oral fluid), generally exceeded those in plasma and peaked at an average concentration of 1215 ng/ml. A substantial intra- and inter-subject variability was observed with this matrix, and values ranged from 50 to 6982 ng/ml MDMA. Somewhat surprisingly, even 4-5h after ingestion, the MDMA levels in sweat only averaged 25 ng/wipe. In addition to this controlled study, data were collected from 19 MDMA-users who participated in a driving simulator study (Study 2), comparing sober non-drug conditions with MDMA-only and multiple drug use conditions. In this particular study, urine samples were used for general drug screening and oral fluid was collected as an alternative to blood sampling. Analysis of oral fluid samples by LC-MS/MS revealed an average MDMA/MDEA concentration of 1121 ng/ml in the MDMA-only condition, with large inter-subject variability. This was also the case in the multiple drug condition, where generally, significantly higher concentrations of MDMA, MDEA and/or amphetamine were detected in the oral fluid samples. Urine screening revealed the presence of combinations such as MDMA, MDEA, amph, cannabis, cocaine, LSD and psilocine in the multiple-drug condition.

Cognitive function and mood in MDMA/THC users, THC users and non-drug using controls

Repeated ecstasy (MDMA) use is reported to impair cognition and cause increased feelings of depression and anxiety. Yet, many relevant studies have failed to control for use of drugs other than MDMA, especially marijuana (THC). To address these confounding effects we compared behavioural performance of 11 MDMA/THC users, 15 THC users and 15 non-drug users matched for age and intellect. We tested the hypothesis that reported feelings of depression and anxiety and cognitive impairment (memory, executive function and decision making) are more severe in MDMA/THC users than in THC users. MDMA/THC users reported more intense feelings of depression and anxiety than THC users and non-drug users. Memory function was impaired in both groups of drug users. MDMA/THC users showed slower psychomotor speed and less mental .exibility than non-drug users. THC users exhibited less mental .exibility and performed worse on the decision making task compared to non-drug users but these functions were similar to those in MDMA/THC users. It was concluded that MDMA use is associated with increased feelings of depression and anxiety compared to THC users and non-drug users. THC users were impaired in some cognitive abilities to the same degree as MDMA/THC users, suggesting that some cognitive impairment attributed to MDMA is more likely due to concurrent THC use.

Dissociable Effects of a Single Dose of Ecstasy (MDMA) on Psychomotor Skills and Attentional Performance

Ecstasy (3,4-methylenedioxymethamphetamine, MDMA) is a psychoactive recreational drug widely used by young people visiting dance parties, and has been associated with poor cognitive function. The current study assessed the influence of a single dose of MDMA 75 mg and alcohol 0.5 g/kg on cognition, psychomotor performance and driving-related task performance. Twelve healthy recreational ecstasy users participated in an experimental study conducted according to a double-blind, double-dummy, placebo-controlled three-way cross-over design. MDMA improved psychomotor performance, such as movement speed and tracking performance in a single task, as well as in a divided attention task. MDMA impaired the ability to predict object movement under divided attention. However, the inability to accurately predict object movement after MDMA may indicate impairment of particular performance skills relevant to driving. There was no effect of MDMA on visual search, planning or retrieval from semantic memory.

Impaired perception of self-motion (heading) in abstinent ecstasy and marijuana users.

RationaleIllicit drug use can increase driver crash risk due to loss of control over vehicle trajectory. This study asks, does recreational use of ±3,4-Methylenedioxymethamphetamine (MDMA; ecstasy) and tetrahydrocannabinol (THC; marijuana) impair cognitive processes that help direct our safe movement through the world?ObjectiveThis study assesses the residual effects of combined MDMA/THC use, and of THC use alone, upon perceived trajectory of travel.MethodsPerception of self-motion, or heading, from optical flow patterns was assessed using stimuli comprising random dot ground planes presented at three different densities and eight heading angles (1, 2, 4 and 8° to the left or right). On each trial, subjects reported if direction of travel was to the left or the right.ResultsResults showed impairments in both drug groups, with the MDMA/THC group performing the worst.ConclusionsThe finding that these psychoactive agents adversely affect heading perception, even in recently abstinent users, raises potential concerns about MDMA use and driving ability.