Adverse effects of Mephedrone


Adverse effects reported by users include sweating, headaches, tachycardia, palpitations, nausea, chest pain, bruxism (teeth grinding), agitation/aggression and paranoia. In addition, nasal insufflation of mephedrone is reported to be associated with significant nasal irritation and pain which has led to some users switching to oral use of mephedrone. Users report increased sexual arousal but there is insufficient information to detect whether this is associated with highrisk sexual behaviour.
Some detailed information on the patterns of acute mephedrone toxicity is available from clinical case series from poisons information services and specialist hospitals in the United Kingdom and Sweden, including one series of analytically confirmed acute mephedrone toxicity from the United Kingdom. In this data, patients typically present with sympathomimetic features (dilated pupils, agitation, tachycardia, hypertension); severe clinical features such as chest pain, significant hypertension, arrhythmias and seizures have been reported in a small number of cases to date. Similar to other stimulant drugs, it is likely that the risk of toxicity is related to the dose of mephedrone used; however there is insufficient information available from toxicity
reports to determine a ‘dose threshold’ and/or whether particular routes of use are more likely to be associated with toxicity. It is possible that certain rare, but clinically significant, severe effects are associated with mephedrone use. However, as experience of the toxicological profile of the drug is currently limited to a few hundred cases it is difficult to be sure.

Data from individuals presenting with acute mephedrone toxicity suggest that the majority of individuals have used at least one other substance together with mephedrone. However there are analytically confirmed cases of lone mephedrone toxicity. This is similar to individuals presenting with acute toxicity related to other stimulant drugs. There are two reported fatalities in which mephedrone appears to be the sole cause of death (one in Sweden and one in the United Kingdom). In addition to these cases, there are at least another 37 deaths in the United Kingdom and Ireland in which mephedrone has been detected in post-mortem blood and/or urine toxicology screening. In some of these cases it is likely that other drugs and/or other medical conditions or trauma may have contributed to or been responsible for death. The inquests into the deaths are pending for the majority of these cases therefore it is not possible at this time to determine the contribution of mephedrone.

Strong craving for the substance is reported by some users’ self-reports, sometimes rated higher than that experienced with other stimulant drugs. This is cited as a main reason for using more mephedrone than intended, and for using for longer periods than planned. Withdrawal symptoms do not appear to be significant for most users with the primary symptoms of nasal congestion and fatigue most probably related to route of use and lack of sleep secondary to staying up late. However the other reported findings, in heavier users, would be consistent with a stimulant withdrawal syndrome. There is some evidence that the drug has a high abuse liability with over 30 % of the UK telephone survey sample reporting three or more DSM criteria
of dependence and being classified as dependent. Tolerance, loss of control, a strong urge to use and using despite problems predominate. In addition, there are reports from the United Kingdom of mephedrone dependence being reported to drug treatment services that suggest psychological rather than physical dependency similar to other stimulant drugs.
No studies have been published investigating the potential for chronic mephedrone toxicity associated with mephedrone use, including reproductive toxicity, genotoxicity and carcinogenic potential. Reports suggest mephedrone may be used as an alternative to illicit stimulants. The reasons given for using mephedrone include: value for money, product purity and consistency as well as the poor availability or low quality of other stimulants (cocaine, ecstasy/MDMA). Some users
noted a preference for mephedrone over other stimulant drugs with data from the UK clubbers rating mephedrone above ecstasy and cocaine for strength and pleasurable high. Mephedrone users in the UK telephone survey reported on the considerable impact mephedrone had on their consumption of cocaine and ecstasy, with approximately two thirds of the sample reporting that they now took less MDMA, and a third reporting that they now consumed less cocaine. Just under half of the group reported they would choose mephedrone over cocaine and only a quarter said that they would take mephedrone over ecstasy. The physical effects reported by mephedrone users are typical of other stimulants and may be particularly similar to MDMA. However, mephedrone’s relatively short duration of action, leading to repeat dosing, is more analogous to cocaine.
In summary, from the data sources available, it appears that the effect profile and clinical presentations of mephedrone intoxications share some features seen with MDMA and some features seen with cocaine. Additionally, there are very limited reports of fatalities directly related to mephedrone. Some users have reported negative effects and in some cases these have required medical attention. Similar to other stimulant drugs, the extent to which users experience problems requires further investigation. Data also suggest that mephedrone has a potential to cause dependency. However, more in-depth studies would be required to explore in
detail the dependence potential of this drug.

Source: excerpt from DEA report 2010

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"After quitting mephedrone, I can't concentrate on anything... I can't understand anything. I'm completely and utterly useless. I stare at the screen at my job, trying to make some sense of the nonsense in front of me. I end up sobbing in the toilets in sh"


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