1-Benzylpiperazine (BZP) is one of a small group of benzyl-substituted piperazines, but a much larger group comprises the phenylpiperazines (see Tables 1 and 2 on EMCDDA webpage). Despite claims by some tablet and capsule suppliers that they are herbal products, piperazine and its derivatives are synthetic substances that do not occur naturally. The large-scale misuse of certain piperazine derivatives (often known as ‘party pills’) started in New Zealand several years ago, but became common in Europe only after 2004. BZP is a central nervous system (CNS) stimulant with around 10 % of the potency of d-amphetamine. Neither BZP nor any other substituted piperazine is listed in the Schedules of the United Nations 1971 Convention on Psychotropic Substances, although several members of this family have been proposed for critical review by WHO in 2009. Following a risk assessment by Europol and the EMCDDA in 2007, a Council Decision of 2008 introduced controls on BZP in the European Union.
One of the phenylpiperazines, 1-(3-chlorophenyl)piperazine (mCPP), has been even more widespread than BZP. By 2006, it was estimated that almost 10 % of illicit tablets sold in the EU, as part of the illicit ecstasy market, contained mCPP. At the end of 2008 and beginning of 2009, this percentage seems to have increased up to 50% in some Member States. However, because mCPP is used as a starting material for the synthesis of several antidepressant drugs (e.g. trazodone), it could not be subjected to formal risk assessment under the terms of the Council Decision 2005/387/JHA of 2005 on the information exchange, risk assessment and control of new psychoactive substances. Apart from mCPP, the next most commonly-found substituted piperazine was 1-(3-trifluoromethyl-phenyl)piperazine (TFMPP), although it was nearly always seen in combination with BZP. Other mixtures of piperazine derivatives became common during 2008, but most consisted of variations of BZP, TFMPP, mCPP and DBZP, sometimes mixed with other substances such as amphetamine, cocaine, ketamine and MDMA.
For more information on this substance see the EMCDDA webpage on BZP and other piperazinesEMCDDA Drug profiles glossary