Designer drugs appear to be increasing in popularity because of easy obtaining on the Internet, the lack of ability to identify the compound(s) in routine toxicology screening and being marketed as ‘legal’ substitute of drugs of abuse. 2,5-dimethoxy-4-chloroamphetamine (DOC) is a substituted alpha methylated phenethylamine and acts as a selective serotonin receptor partial agonist. There is limited literature on this particular compound, which is rarely encountered in biological matrices, and only one case-report attributed death to the use of this drug alone. We present five cases of non-fatal exposure to DOC with sever clinical symptoms (ages range 18–23years). DOC was identified using data from LC/UV and GC/MS screening procedures. DOC in plasma and urine samples was quantified using a validated LC/MS/MS method and results showed that DOC plasma concentrations were less than 18μg/L and DOC urine concentrations ranged from 300 to 1300μg/L. This is the first documentation of DOC consumption in France, and in 4 cases, the patients believed that they were ingesting LSD. This indicates the emergence of designer drugs use as ‘legal’ LSD substitutes and we are concerned by the discrepancies in legal status of such compounds in the EU, which limit the effectiveness of drug enforcement policies.