Drug users in the Netherlands increasingly buy drugs online, especially new psychoactive substances. Analysis of 32,663 drug samples from 2013 to 2016, including 928 bought online, found that online purchases rose from 1.4% to 4.1% of samples. Purity and adulteration showed no large differences between online and offline drugs for most substances, though small variations existed for some: 4-FA was 59% pure online versus 52% offline, while MDMA powder was 45% pure online versus 61% offline. Online prices were 10–23% higher than offline for six of ten substances.
Young adults who use ecstasy in the United Kingdom and the Netherlands show three similar patterns of polydrug use: traditional polydrug use (UK 28%, NL 40%), stimulant and ketamine use (UK 48%, NL 52%), and extensive polydrug use involving stimulants, depressants, and psychedelics (UK 24%, NL 8%). UK users more often consume MDMA as powder/crystalline at higher doses, while Dutch users prefer tablets. Most respondents in both countries intend to reduce but not quit their use. The patterns are structurally similar across countries, though individual substance frequencies and preferred MDMA form differ.
In the three days after using ecstasy/MDMA, young adults who regularly use the drug report a small but significant drop in mental well-being, even after accounting for other substance use, sleep, and baseline depression or anxiety. Cocaine co-use and poor sleep further worsened the effect. No similar drop was seen after use of other common substances. The findings suggest the post-acute mood decline is specifically linked to ecstasy/MDMA, not just party or lifestyle factors.