In recent years, the increasing use tendency of NPS has motivated both awareness and concern about their identification and potential harmfulness. Synthetic cathinones represent a significant proportion of the NPS available and methylone is one of the most frequently found in Europe.

The aim of the present study is to determine methylone presence and characteristics from the samples analyzed by Energy Control between the years 2009 and 2015 in Spain.

From all 21,198 samples analyzed from august 2009 to august 2015, only those in which methylone was found are studied (n=140). The samples have been analyzed by Energy Control, a spanish harm-reduction NGO that offers to users the possibility of analyzing the substances they intend to consume. The analysis is done by gas chromatography–mass spectrometry.

From the 140 samples containing methylone, 87 were handled as methylone, 20 as MDMA, 8 as other synthetic cathinones and 25 as other substances. The peak of consume was registered in 2011 with 41 samples then the number decreased until 10 samples in 2015.

Results suggest that methylone is most frequently handled as methylone or as MDMA and that its consumption could be decreasing. Further pharmacokinetic, pharmacodynamic, clinical and epidemiological studies should be conducted to enhance the knowledge not only about methylone consumption, but also about synthetic cathinones in general in order to assess their potential risk and study the complications and its management.