BZP-party pills: a review of research on benzylpiperazine as a recreational drug

Molecular Imprinting of Benzylpiperazine: A Comparison of the Self-Assembly and Semi-Covalent Approaches

Molecularly imprinted polymers (MIPs) for benzylpiperazine (BZP, 1), an illicit designer drug, were developed by using both self-assembly and semi-covalent approaches. From an array of potential functional monomers (FMs) and using a combination of pre-synthetic interaction studies (by molecular modelling and NMR analysis) and binding assays, the highest performing self-assembly 1-MIPs were confirmed to result from methacrylic acid (7) as FM, ethylene glycol dimethacrylate (EGDMA) or trimethylolpropane trimethacrylate (TRIM) as crosslinkers and chloroform as the porogen and rebinding solvent at template (T): FM ratios of 1:1 and 1:2, giving imprinting factors (IF) 3 to 7. The semi-covalent 1-MIPs were designed using benzylpiperazine (4-vinylphenyl) carbamate (16) as the template-monomer adduct in combination with either EDGMA or TRIM. Our comparative analysis showed the semi-covalent polymers to have a stronger affinity for 1 (significantly lower K_d values and higher IFs) and faster uptake than the self-assembly systems. Both approaches have comparable cross-reactivity: marginal to low against cocaine (17) and morphine (18) and high against ephedrine (19) and phenylpiperazine (20). They also have comparable selectivity: highly selective towards 1 against 17, moderate against 18 and non-selective against 19. EGDMA-based self-assembly MIPs displayed a greater imprinting effect (higher IFs and NIP-to-MIP K_d ratios) than TRIM-based MIPs, while the TRIM-based semi-covalent MIP outperformed its EGDMA-based equivalent. By virtue of its modest selectivity against the test illicit drugs, 1-MIPs could potentially be used as a dummy MIP for the broad-based capture and enrichment of illicit drug blends for subsequent laboratory analysis.

An Update on the Implications of New Psychoactive Substances in Public Health

The emergence of new psychoactive substances has earned a great deal of attention, and several reports of acute poisoning and deaths have been issued involving, for instance, synthetic opiates. In recent years, there have been profound alterations in the legislation concerning consumption, marketing, and synthesis of these compounds; rapid alert systems have also been subject to changes, and new substances and new markets, mainly through the internet, have appeared. Their effects and how they originate in consumers are still mostly unknown, primarily in what concerns chronic toxicity. This review intends to provide a detailed description of these substances from the point of view of consumption, toxicokinetics, and health consequences, including case reports on intoxications in order to help researchers and public health agents working daily in this area.

Comparison of LC-MS and LC-DAD Methods of Detecting Abused Piperazine Designer Drugs

Recreational use of piperazine designer drugs is a serious threat to human health. These compounds act on the body in a similar fashion to illegal drugs. They induce psychostimulatory effects as well as visual and auditory hallucinations to varying degrees. In many cases of poisoning and deaths, the presence of two or even several psychoactive substances have been demonstrated. Piperazine derivatives are often found in such mixtures and pose a great analytical problem during their identification. Additionally, some piperazine derivatives can be detected in biological material as a result of metabolic changes to related drugs. Therefore, it is necessary to correctly identify these compounds and ensure repeatability of determinations. This article presents a comparison of the methods used to detect abused piperazine designer drugs using liquid chromatography in combination with a diode-array detector (LC-DAD) or mass spectrometer (LC-MS). Each of methods can be used independently for determinations, obtaining reliable results in a short time of analysis. These methods can also complement each other, providing qualitative and quantitative confirmation of results. The proposed methods provide analytical confirmation of poisoning and may be helpful in toxicological diagnostics.

Rapid Targeted Method of Detecting Abused Piperazine Designer Drugs

Piperazine derivatives belong to the popular psychostimulating compounds from the group of designer drugs. They are an alternative to illegal drugs such as ecstasy and amphetamines. They are being searched by consumers for recreational use due to their stimulating and hallucinogenic effects. Many NPS-related poisonings and deaths have been reported where piperazines have been found. However, a major problem is the potential lack of laboratory confirmation of the involvement of piperazine derivatives in the occurrence of poisoning. Although many methods have been published, piperazine derivatives are not always included in a routine analytical approach or targeted toxicological analysis. There is an increasing need to provide qualitative evidence for the presence of piperazine derivatives and to ensure reproducible quantification. This article describes a new rapid method of detecting piperazine derivatives in biological material, using LC-MS. All target analytes were separated in a 15 min run time and identified based on the precursor ion, at least two product ions, and the retention time. Stable isotopically labeled (SIL) internal standards: BZP-D7, mCPP-D8 and TFMPP-D4 were used for analysis, obtaining the highest level of confidence in the results. The proposed detection method provides the analytical confirmation of poisoning with piperazine designer drugs.

Piperazine derivatives as dangerous abused compounds

Piperazine derivatives are a group of compounds with a psychostimulant effect. They are an alternative to illegal drugs. They are being searched for recreational use due to their psychoactive and hallucinogenic effects. The high popularity of these compounds can be noticed all over the world due to easy purchase, lack of legal regulations and incorrect assessment of the safety of use. The recreational use of piperazine derivatives can often result in chronic and acute health problems and additionally with unpredictable remote effects. It is also common to take mixtures of psychoactive compounds. This hinders the correct diagnosis and treatment of patients with poisoning. The presented work is an illustration of the wide problem of piperazine derivatives abuse. The health effects and the possibility of identifying these compounds in preparations and biological material are described.

The Novel Psychoactive Substances in the UK Project: empirical and conceptual review work to produce research recommendations

Background

Although illegal drug use has largely been declining in the UK over the past decade, this period has witnessed the emergence of a range of novel psychoactive substances (NPS) (‘legal highs’). These are new, mostly synthetic, substances that mimic the effects of existing drugs). Despite there being many causes for concern in relation to NPS, there has been little prior study of the burden associated with their use in public health terms. Clarity is lacking on research priorities in this rapidly developing literature.

Objectives

To inform the development of public health intervention research on NPS by reviewing existing data on their use, associated problems and potential responses to such problems.

Design

A scoping review and narrative synthesis of selected bodies of evidence was undertaken to summarise and evaluate what is known about NPS use and the related harms of, and responses to, such use. Relevant literature was identified from electronic databases (covering January 2006 to June 2016 inclusive), Google (Google Inc., Mountain View, CA, USA), relevant websites and online drug forums and by contacting experts. Articles were included if they were primary studies, secondary studies involving the analysis and interpretation of primary research or discussion papers. A conceptual framework postulating an evidence-informed public health approach to NPS use in the UK was developed through a pragmatic literature review, the iterative development of concepts and finalisation in light of the results from the empirical review work. The process also involved feedback from various stakeholders. Research recommendations were developed from both strands of work.

Results

A total of 995 articles were included in the scoping review, the majority of which related to individual-level health-related adverse effects attributable to NPS use. The prevalence of lifetime NPS use varied widely between (e.g. with higher prevalence in young males) and within population subgroups. The most commonly reported adverse effects were psychiatric/other neurological, cardiovascular, renal and gastrointestinal manifestations, and there is limited evidence available on responses. In these and other respects, available evidence is at an early stage of development. Initial evidence challenges the view that NPS should be treated differently from other illicit drugs. The conceptual framework indicated that much of the evidence that would be useful to inform public health responses does not yet exist. We propose a systems-based prevention approach that develops existing responses, is multilevel and life course informed in character, and emphasises commonalities between NPS and other legal and illegal drug use. We make 20 recommendations for research, including nine key recommendations.

Limitations

Scoping reviews do not interrogate evidence in depth, and the disjunction between the scoping review and the conceptual framework findings is worthy of careful attention.

Conclusions

Key research recommendations build on those that have previously been made and offer more evidence-based justification and detail, as previous recommendations have not yet been acted on. The case for decision-making on commissioning new research based on these recommendations is both strong and urgent.

Future work

The validity of recommendations generated through this project could be enhanced via further work with research commissioners, policy-makers, researchers and the public.

Study registration

The systematic review element of this study is registered as PROSPERO CRD42016026415.

Funding

The National Institute for Health Research Public Health Research programme.

Benzylpiperazine: "A messy drug"

Designer drugs are synthetic structural analogues/congeners of controlled substances with slightly modified chemical structures intended to mimic the pharmacological effects of known drugs of abuse so as to evade drug classification. Benzylpiperazine (BZP), a piperazine derivative, elevates synaptic dopamine and serotonin levels producing stimulatory and hallucinogenic effects, respectively, similar to the well-known drug of abuse, methylenedioxymethamphetamine (MDMA). Furthermore, BZP augments the release of norepinephrine by inhibiting presynaptic autoreceptors, therefore, BZP is a "messy drug" due to its multifaceted regulation of synaptic monoamine neurotransmitters. Initially, pharmaceutical companies used BZP as a therapeutic drug for the treatment of various disease states, but due to its contraindications and abuse potential it was withdrawn from the market. BZP imparts predominately sympathomimetic effects accompanied by serious cardiovascular implications. Addictive properties of BZP include behavioral sensitization, cross sensitization, conditioned place preference and repeated self-administration. Additional testing of piperazine derived drugs is needed due to a scarcity of toxicological data and widely abuse worldwide.

An overview of recent developments in the analytical detection of new psychoactive substances (NPSs)

New psychoactive substances (NPSs), sometimes referred to as "legal highs" in more colloquial environments/the media, are a class of compounds that have been recently made available for abuse (not necessarily recently discovered) which provide similar effects to the traditional well studied illegal drugs but are not always controlled under existing local, regional or international drug legislation. Following an unprecedented increase in the number of NPSs in the last 5 years (with 101 substances discovered for the first time in 2014 alone) its, occasionally fatal, consequences have been extensively reported in the media. Such NPSs are typically marketed as 'not for human consumption' and are instead labelled and sold as plant food, bath salts as well as a whole host of other equally nondescript aliases in order to bypass legislative controls. NPSs are a new multi-disciplinary research field with the main emphasis in terms of forensic identification due to their adverse health effects, which can range from minimal to life threatening and even fatalities. In this mini-review we overview this recent emerging research area of NPSs and the analytical approaches reported to provide detection strategies as well as detailing recent reports towards providing point-of-care/in-the-field NPS ("legal high") sensors.

Piperazine derivatives of boronic acids – potential bifunctional biologically active compounds

The combination of a piperazine and boronic groups within one molecule can result in a totally novel biological activity.

[Emergence of novel psychoactive substances among clients of a needle exchange program in Budapest, Hungary]

In this paper the authors summarize experience of a drug service provider with the injecting use of novel psychoactive substances. Among clients of the needle exchange programme of Blue Point Drug Counselling and Outpatient Centre, the authors observed the spread of the novel substances since 2009. The extensive spread of the novel substances caused substantial change in injecting use patterns, thus in the usage of the needle exchange programme. The novel psychoactive substances appeared consecutively, so that this setting gave a unique opportunity to observe and track the emergence of these substances. The authors summarize the characteristics which are important for medical practice (risks, frequent use, severe psychopathological conditions) as well as special risks associated with these substances (substances with unknown composition and effect). They highlight the importance and role of the early warning system, monitoring the online sources of information and testing of samples containing novel psychoactive substances.

The impact of the prohibition of benzylpiperazine (BZP) "legal highs" on the availability, price and strength of BZP in New Zealand

BACKGROUND

Legal highs containing benzylpiperazine (BZP) were widely sold in New Zealand until BZP was prohibited in 2008. We examined the impact the prohibition had on the availability and price of BZP over following years.

METHODS

Two national population surveys of BZP use were conducted in 2006 and 2009. Four annual targeted surveys of frequent drug users (FDU) were conducted from 2007-2010. Availability and price measures were obtained. Inflation-adjusted real retail prices were calculated. Other drug markets were monitored as quasi-controls.

RESULTS

The proportion of BZP users from the general population who considered the availability of BZP to be 'very easy' declined from 76% in 2006 to 21% in 2009. The proportion who thought BZP had become 'harder' to obtain increased from 5% in 2006 to 71% in 2009. The proportion who reported the price of BZP was 'higher' increased from 27% in 2006 to 51% in 2009. FDU who considered the availability of BZP to be 'very easy' declined from 98% in 2007 to 15% in 2008, and then increased to 42% by 2010. The real retail price of a BZP tablet increased from $9.86 in 2007 to $15.83 in 2010. The proportion who considered the price of BZP to be 'increasing' rose from 3% in 2007 to 47% in 2010.

CONCLUSIONS

The availability of BZP declined immediately following its prohibition. Availability recovered in subsequent years, but not to the pre-prohibition legal level. The price of BZP increased slowly over a number of years following the prohibition.

'Designer drugs': update on the management of novel psychoactive substance misuse in the acute care setting

The use of novel psychoactive substances ('legal highs' or 'designer drugs') is increasing worldwide. Patients misusing such substances have been reported to experience severe or prolonged side effects requiring admission to acute or critical care wards. These complications can be life threatening if misdiagnosed or mismanaged. As physicians have traditionally had less involvement with the management of such patients compared with their colleagues in emergency departments an update in the management of such patients is indicated. Here we present a summary of the management of those novel substances with the potential for serious complications based on a review of current literature.

Nephrotoxic effects of designer drugs: synthetic is not better!

Designer drugs are synthetic, psychoactive substances with similar structures and activity to existing scheduled drugs or controlled chemical compounds. The use of these drugs is not generally considered illegal and they cannot be detected using standard toxicology tests--essentially they are considered to be 'legal highs'. Over the past several years, increasing numbers of designer drugs have become available. These drugs are classified as amphetamine derivatives, phenylpiperazine derivatives, synthetic cathinones, synthetic cannabinoids, phencyclidine derivatives and synthetic opioids. Although euphoria is the desired effect, neuropsychiatric and cardiac manifestations are frequently observed in individuals using these drugs at high doses or using drugs that are contaminated with other substances. Some designer drugs are also associated with adverse renal effects, including acute kidney injury from pigment nephropathy, acute tubular necrosis, obstructive nephropathy and hyponatraemia. The misuse of these drugs should be recognized and clinicians made aware of the potential for acute nephrotoxicity as the health burden of these compounds increases.

The new psychoactive substances regime in New Zealand: a different approach to regulation

The New Zealand government has proposed a new psychoactive substances regime, which will place the onus onto manufacturers to prove that their products pose a low risk of harm, prior to receiving approval which allows the products to be legally manufactured and sold. This is an innovative and unique development in the regulation of emerging psychoactive substances, and offers an alternative response to prohibition. The details of the new regime and how it will operate are now emerging, and this offers an opportunity to critically explore some of the issues related to the proposed new regime and to speculate on some of the outcomes. This paper brings together a group of New Zealand based researchers from a range of disciplines with experience of 'legal high' research to discuss this innovative new regime.

Screening of methylenedioxyamphetamine- and piperazine-derived designer drugs in urine by LC-MS/MS using neutral loss and precursor ion scan

This study describes a method for the screening of methylenedioxyamphetamine- and piperazine-derived compounds in urine by liquid chromatography-tandem mass spectrometry. These substances, characterized by possessing common moieties, are screened using precursor ion and neutral loss scan mode and then quantified in multiple reaction monitoring acquisition mode. Based on the product-ion spectra of different known molecules, chosen as 'model', characteristic neutral losses and product ions were selected: piperazines were detected in precursor ion scan of m/z 44 and neutral loss of 43 and 86 while amphetamines in precursor ion scan of m/z 133, 135 and 163. The applicability of the screening approach was studied in blank urine spiked with selected analytes and processed by solid-phase extraction. Linearity, matrix effect, precision, accuracy, limits of detection and limits of quantification were evaluated both for the screening and the quantification methods. The ability of the screening method to provide semi-quantitative data was demonstrated. This method appears to be a useful tool for the identification of designer drugs derived from piperazines or methylenedioxyamphetamines and can be potentially applied to other drug classes.

The impact of the prohibition of benzylpiperazine (BZP) 'legal highs' on the prevalence of BZP, new legal highs and other drug use in New Zealand

BACKGROUND

Benzylpiperazine (BZP) is the psychoactive ingredient in a range of 'legal highs' sold worldwide. BZP was prohibited in New Zealand in 2008.

AIM

To investigate the impact of the prohibition of BZP legal highs on the prevalence of BZP, replacement legal highs and other drugs.

METHODS

A population survey of BZP and other drugs was conducted in 2006 (while BZP was legal) and repeated in 2009 (+12 months after BZP was prohibited). Respondents were asked to provide the reason(s) why they had stopped using BZP. Annual surveys of frequent drug users were conducted from 2006 to 2010.

RESULTS

Last year prevalence of BZP among the general population fell from 15.3% in 2006 to 3.2% in 2009. The most common reasons for stopping BZP use in 2008 were 'it's illegal now' (43%), 'just experimenting' (26%), 'don't know where to get it now it's illegal' (24%) and 'bad hangover effect' (18%). Three per cent of the general population had used any new legal high in 2009. Use of BZP declined among frequent methamphetamine users from 32% in 2006 to 7% in 2010; among frequent ecstasy users from 65% in 2006 to 11% in 2010; and among frequent injecting drug users from 30% in 2007 to 20% in 2010. The use of new legal highs in 2010 was lower than the former use of BZP in 2006.

CONCLUSIONS

Unpleasant side-effects and the prohibition contributed to a decline in BZP use. The overall level of legal high use was lower following the prohibition of BZP.

Determination of 32 cathinone derivatives and other designer drugs in serum by comprehensive LC-QQQ-MS/MS analysis

Recently, clandestine drug lab operators have attempted to bypass controlled substances laws and regulations with "designer" compounds chemically and pharmacologically similar to controlled substances. For example, "bath salts" have erupted onto the scene as "legal highs" containing cathinone analogs that have produced severe side effects in users worldwide. These products have sparked concern among law enforcement agencies, and emergency bans have been placed on the sale of such items. Despite the increasing number of designer drugs available, there are few comprehensive screening techniques for their detection and quantification in biological specimens. The liquid chromatography triple quadrupole tandem mass spectrometry (LC-QQQ-MS/MS) method presented here encompasses over thirty important compounds within the phenethylamine, tryptamine, and piperazine designer drug classes. Analytes were determined by LC-QQQ-MS/MS in the multiple-reaction monitoring mode after mixed-mode solid-phase extraction. The bioanalytical method was fully validated according to recommended international guidelines. The assay was selective for all analytes with acceptable accuracy and precision. Limits of quantification were in the range of 1-10 ng/mL for each compound with limits of detection near 10 pg/mL. In order to evaluate its applicability in a forensic toxicological setting, the validated method was used to analyze post-mortem specimens from two cases that were suspected of containing designer drugs. The method was able to identify and quantify seven of these compounds at concentrations as low as 11 ng/mL. The method should have wide applicability for rapid screening of important new drugs of abuse at high sensitivity in both post- and ante-mortem forensic analysis.

Piperazine compounds as drugs of abuse

Synthetic drugs are among the most commonly abused drugs in the world. This abuse is widespread among young people, especially in the dance club and rave scenes. Over the last several years, piperazine derived drugs have appeared, mainly available via the internet, and sold as ecstasy pills or under the names of "Frenzy", "Bliss", "Charge", "Herbal ecstasy", "A2", "Legal X" and "Legal E". Although in the market piperazine designer drugs have the reputation of being safe, several experimental and epidemiological studies indicate risks for humans. Piperazine designer drugs can be divided into two classes, the benzylpiperazines such as N-benzylpiperazine (BZP) and its methylenedioxy analogue 1-(3,4-methylenedioxybenzyl)piperazine (MDBP), and the phenylpiperazines such as 1-(3-chlorophenyl)piperazine (mCPP), 1-(3-trifluoromethylphenyl)piperazine (TFMPP), and 1-(4-methoxyphenyl)piperazine (MeOPP). Toxicokinetic properties, including metabolic pathways, actions and effects in animals and humans, with some hypothesis of mechanism of action, and analytical approaches for the identification of these drugs are summarized in this review.

Linking the pharmacological content of ecstasy tablets to the subjective experiences of drug users

RATIONALE

Most studies on the subjective effects of ecstasy are based on the assumption that the substance that was taken is 3,4-methylenedioxymethamphetamine (MDMA). However, many tablets sold as ecstasy contain other substances and MDMA in varying doses. So far, few attempts have been made to take this into account while assessing subjective effects.

OBJECTIVES

This study aims to link the pharmacological content of tablets sold as ecstasy to the subjective experiences reported by ecstasy users.

METHODS

Self-reported effects on ecstasy tablets were available from 5,786 drug users who handed in their tablets for chemical analysis at the Drug Information and Monitoring System (DIMS) in the Netherlands. Logistic regression was employed to link the pharmacological content of ecstasy tablets to the self-reported subjective effects and compare effects with MDMA to other substances present.

RESULTS

MDMA showed a strong association with desirable subjective effects, unparalleled by any other psychoactive substance. However, the association of MDMA was dose-dependent, with higher doses (>120 mg/tablet) likely to evoke more adverse effects. The novel psychostimulants mephedrone and p-fluoroamphetamine were considered relatively desirable, whereas meta-chlorophenylpiperazine (mCPP) and p-methoxymethamphetamine (PMMA) were strongly associated with adverse subjective effects. Also, 3,4-methylene-dioxyamphetamine (MDA) and benzylpiperazine (BZP) were not appreciated as replacement for MDMA.

CONCLUSION

Linking the pharmacological content of ecstasy sold on the street to subjective experiences contributes to a better understanding of the wide range of subjective effects ascribed to ecstasy and provides a strong rationale for the prolonged endurance of MDMA as the key ingredient of the ecstasy market.