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Drug Science

Variability in content of MDMA tablets collected in the UK between 2001 and 2018 - a potential risk to users?


a big pile of different colour pills

As summer approaches and with an increasing number of outdoor events in the calendar, the pop-up drug scene comes back into focus. As with previous years, MDMA (ecstasy), the most prominent drug at festivals and clubs, is likely to dominate again.


Tragedy has struck down a number of young lives with MDMA related deaths increasing over the past years. But is this simply a result of higher strength ecstasy tablets or over-consumption? Perhaps more is at play.


Research by ASI, TICTAC and Queen Mary University of London (QMUL) has identified not only does the amount of MDMA significantly vary in ecstasy tablets from the same batch, but there is also a large variance in the length of time it takes ecstasy tablets to release MDMA into the body (bioavailability). Add these to MDMA’s idiosyncratic toxicity (people react differently to the same dose of MDMA) and a trend of higher dose ecstasy tablets, and it really can be a game of Russian roulette for both experienced and new users. Yes, the vast majority of people taking MDMA do not come to harm, but there is at present no way to predict, determine or prevent who will. In research findings just published in the journal Drug Testing and Analysis, ASI, TICTAC and QMUL analysed over 650 seized ecstasy tablets and established that tablets from the same batch can contain concentrations of MDMA which vary by more than 250%.


For the first time, these experiments also revealed that ecstasy tablets disintegrate at different rates. ‘Fast releasing’ tablets released 95% of their MDMA into the body within 30 minutes while for ‘slow releasing’ tablets, this took 100 minutes. This effect increases the likelihood of double dosing (taking a second dose before the effects of the first dose are fully experienced). The research also confirmed the general trend of increasingly higher dosage illicit drugs in circulation, with older tablets containing less MDMA than more recent tablets, as reported by drug testing organisation The Loop.


These combined risks – higher strength MDMA tablets, idiosyncratic toxicity, within batch strength variance and varying rates of release, need to be considered by those intending to use MDMA and by those providing drug advice. Potency and toxicity cannot be predicted, even when drug testing for users is employed.


‘Our research clearly demonstrates that taking MDMA is a far more risky activity than perhaps thought’ said Dr Lewis Couchman, ASI’s Research Director, ‘it is prone to unpredictable dosing with toxic effects and potentially lethal consequences, of which users and drug workers need to be aware and should be warned. This unpredictability is a strong argument for the immediate and widespread roll-out of drug testing services within city centres, clubs, and festivals, without which users remain in the dark and highly vulnerable. A recent analysis of The Loop’s drug testing work at festivals can be found here, and an earlier DrugScience blog on the topic here.



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