Psychiatrists document adverse effects of mephedrone

The researchers studied 20 people who arrived at the emergency departments and acute mental health services in Edinburgh and Falkirk between January and June 2010, seeking treatment after taking mephedrone. Their study is published in the June issue of The Psychiatrist.

17 of the 20 patients were men. The patients were aged between 19 and 59, with most (14 of the 20) falling in the 19-29 age group. Only five people had taken mephedrone for the first time – the rest reported regular or heavy use of the drug before arriving at the hospital.

The most common psychological symptom was agitation, reported by 70% of the patients. In most people, the agitation was severe and accompanied by either aggression or abnormal behaviour.

Eight of the patients (40%) developed psychotic symptoms, including hallucinations and delusions. Of these, 7 (88%) said they had used mephedrone either daily or heavily for the last 4 weeks, and 8 (75%) had a previous history of psychotic illness or depression.

Four of the patients (20%) had acute low mood and suicidal thoughts – which had not been present before they had taken the mephedrone. Tragically, one patient died by suicide.

Mephedrone (4-methylmethcathinone) became controlled as a Class B drug in April 2010. Before this, it was marketed as a ‘legal high’ – a legal alternative to cocaine and amphetamine – and could be purchased online and in specialised ‘head’ shops. Mephedrone use in the UK grew rapidly in 2009 and early 2010, with one survey finding it to be the fourth most used drug after cannabis, ecstasy and cocaine.

Dr Mark Taylor, consultant psychiatrist at NHS Lothian who led the research, said: “Mephedrone is derived from cathinone, the active ingredient of the African shrub khat. Cathinone is structurally very similar to amphetamine, and it would appear that mephedrone also produces the same negative psychological side-effects – particularly in those people with a history of mental illness.”

The researchers acknowledge the limitations of their study, including the fact they relied on the patients to self-report how much mephedrone they had taken. However, Dr Taylor concluded: “Despite these limitations, it is clear that mephedrone use can result in both physical and mental harm – similar to that caused by other controlled stimulant drugs.

“The UK Advisory Council on the Misuse of Drugs has been criticised for prematurely recommending that mephedrone be classified as a Class B drug, but our data would suggest that mephedrone use can have serious harmful consequences. However, market forces have meant that as soon as one substance is made illegal, similar alternatives are produced. More work needs to be done to determine the risks posed by mephedrone and other so-called ‘legal highs’ – just because something is legal does not mean it is safe.”

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Mackay K, Taylor M and Bajaj N. The adverse consequences of mephedrone use: a case series. The Psychiatrist 2011; 35:203-205