The impact of New Zealand's 2008 prohibition of piperazine-based party pills on young people's substance use: results of a longitudinal, web-based study.

BACKGROUND: The last decade has seen the emergence of a new phenomenon in recreational substance use with the availability of herbal and synthetic, unregulated, psychoactive drugs in the market place; alongside this, international concern has developed in relation to their use and associated harms. New Zealand (NZ) was one of the first countries to experience this new phenomenon, with products containing chemicals of the piperazine group - mainly benzylpiperazine (BZP) and trifluoromethylphenylpiperazine (TFMPP). In 2008, the NZ Government prohibited these substances, but allowed a 6-month amnesty period for possession. Our study aimed to obtain a measure of change in BZP use over time. METHODS: This study used a longitudinal, web-based survey, with data collected at two time points from the same participants. The first survey was carried out 3 months after BZP prohibition, and included retrospective questions for the 6 months preceding the survey. The second survey was conducted 9 months after prohibition and also included retrospective questions for the 6 months preceding the survey. RESULTS: 273 sets of paired data were identified. The use of BZP party pills (p Language: en