Levamisole in Illicit Trafficking Cocaine Seized: A One-Year Study

Abstract

Cocaine use is increasing around the world and its purity is frequently altered through dilution, substitution, contamination, and adulteration. Sugars, talc, starch, and carbonates represent the principal diluents of cocaine, while phenacetin, levamisole, caffeine, and lidocaine are its major adulterants in Europe. Levamisole is used because it is an odorless powder, with physical properties similar to cocaine, and it has reasonable cost and availability, being widely used in veterinary medicine. For this study, we analyzed 88 cocaine samples. The seized cocaine analyzed showed an average purity of 55% and the most frequent adulterants identified were: levamisole (31.8%), caffeine (6.8%), lidocaine (2.3%), acetaminophen (2.3%), and phenacetin (1.1%). Our aim is the study of the presence of levamisole, over other adulterants in seized cocaine samples, due to its recognized human toxicity. The chronic use of levamisole-adulterated cocaine represents a serious public health issue because it may be responsible for side-effects such as dermal vasculopathy, leukoencephalopathy, leukopenia, agranulocytosis, pulmonary hemorrhage, multiple emboli, and several other effects. Moreover, aminorex can cause idiopathic pulmonary hypertension, presenting another harmful and mostly lethal side-effect from cocaine cut with levamisole. In conclusion, levamisole determination should be performed in routine toxicological analysis in deaths due to cocaine use.

Cocaine adulteration with the anthelminthic tetramisole (levamisole/dexamisole): Long‐term monitoring of its intake by chiral LC–MS/MS analysis of cocaine‐positive hair samples

“…10 Levamisole has been detected since 2004 in seized cocaine samples with increasing trend. 1,[6][7][8][9] However, a recent study from Austria, reports on a decreasing trend in 2017 compared to 2015 and 2016. 11 A similar trend was observed from local evaluations at the drug testing center for drug users in Zurich, Switzerland.…”

“…1,[6][7][8][9] One pharmacological rationale for the addition of levamisole is that it may have cocaine-like action by inhibition of noradrenaline uptake. 1,[6][7][8][9] One pharmacological rationale for the addition of levamisole is that it may have cocaine-like action by inhibition of noradrenaline uptake.…”

“…1,[6][7][8][9] One pharmacological rationale for the addition of levamisole is that it may have cocaine-like action by inhibition of noradrenaline uptake. 1,[6][7][8][9] However, a recent study from Austria, reports on a decreasing trend in 2017 compared to 2015 and 2016. 1,[6][7][8][9] However, a recent study from Austria, reports on a decreasing trend in 2017 compared to 2015 and 2016.…”

“…11 A similar trend was observed from local evaluations at the drug testing center for drug users in Zurich, Switzerland. 6,9,15 From few recent studies using chiral analytical methods, it is evident, that not only levamisole but also tetramisole and non-racemic mixtures of PTHIT have been detected in seized cocaine samples from mid-2010 16, 17 and in urine samples of cocaine users. [12][13][14] Most importantly, the vast majority of studies presented in the literature testing for levamisole have been conducted by achiral analysis being unable to distinguish between levamisole and the racemate tetramisole (levamisole/ dexamisole).…”

“…isomer of phenyltetraimidazothiazole (S-PTHIT), has been detected as the main adulterant. 1,[6][7][8][9] One pharmacological rationale for the addition of levamisole is that it may have cocaine-like action by inhibition of noradrenaline uptake. 10 Levamisole has been detected since 2004 in seized cocaine samples with increasing trend.…”