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This health-endangering practice by dealers has now been investigated at the MedUni Vienna’s Centre for Physiology and Pharmacology.

(Vienna, 9th January 2014) An alarming discovery: over 70 per cent of the samples that have previously been sold as cocaine not only contained the drug itself, but also a veterinary worming medicine that is harmful to humans. This health-endangering practice by dealers has now been investigated at the MedUni Vienna’s Centre for Physiology and Pharmacology.

Anyone who believes that cocaine is a “pure” substance is virtually always wrong. That’s because more than 90 per cent of the cocaine sold on the streets is cut with different “fillers”. And almost three-quarters of the samples are cut with Levamisol – a worming medicine used for horses and other even-toed ungulates that is harmful to humans.

While dealers are only looking to boost their profits by “cutting” an addictive drug, the addition of the veterinary medicine Levamisol achieves an additional effect: after consumption, the body metabolises Levamisol into aminorex. This equally harmful substance has a strongly amphetamine-like effect on drug users. Dealers are therefore making use of a phenomenon that is already known from horse racing.

This finding represents the cornerstone of a study that has just been published in a special issue of the highly respected journal "Neurochemistry International". The study involved researchers at the MedUni Vienna's Centre for Physiology and Pharmacology within the Institute of Pharmacology (led by: Harald Sitte) in collaboration with the “checkIt!” drugs project at the KILM Clinical Institute of Laboratory Medicine (scientific chief: Rainer Schmid) and a research group from the University of Vienna (led by: Gerhard Ecker).
The study began with the ongoing investigation of narcotics by “checkIt!”, a Vienna-based information and advice centre. In previous years, it has continuously found huge additives of Levamisol and therefore initiated the study.

Study contradicts previous scientific assumptions
“The exciting thing is that we have two completely different classes of substance here that science has previously assumed would be incompatible with drug misuse due to their antagonistic effects," says Harald Sitte from the MedUni Vienna. Lead researchers Tina Hofmaier and Oliver Kudlacek were also able to explain why this is not the case with the simultaneous intake of cocaine and Levamisol: the effect of aminorex – the metabolite of Levamisol – starts to work while the effect of cocaine is wearing off. This prolongs the effect that drug users anticipate from cocaine.

Prevention and education offer effective protection
The study once again confirms that drugs often contain more than drug users think they do. The precise mechanisms and effects of many substance combinations have however so far only been partially explained from a scientific perspective. What is clear is that cocktails of drugs are generally more dangerous than the individual substances. Says Sitte: “This is also why prevention and education are so important in the context of drug misuse."

Service: Neurochemistry International
“Aminorex, a metabolite of the cocaine adulterant levamisole, exerts amphetamine like actions at monoamine transporters.” Tina Hofmaier, Anton Luf, Amir Seddik, Thomas Stockner, Marion Holy, Michael Freissmuth, Gerhard F. Ecker, Rainer Schmid, Harald H. Sitte, Oliver Kudlacek. Neurochemistry International (2013),