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BZP
1-Benzylpiperazine
A2, Legal X, Pep X, Party pillsOpen in Piru
BZP is benzylpiperazine, a synthetic piperazine-class stimulant with euphoriant effects broadly similar to amphetamines1. Many suppliers marketed it as “legal Ecstasy”1 and became one of the first widely promoted research chemicals, but later fell out of popularity. Reported adverse outcomes include a case of acute renal failure in a 17-year-old male after consumption of five BZP tablets and a small amount of alcohol1, and seizures1; the free-base form is corrosive and can cause burns1.
Dosage & Duration
Dosage
Doses are population estimates that vary widely between individuals.
Threshold~40 mg
Light40-70 mg
Moderate70-100 mg
Strong100-130 mg
Heavy130+ mg
Duration
Onset30-45 minutes
After Effects2-4 hours
Total4-6 hours
Subjective Effects
Subjective Effects not written up yet
Pharmacology
Pharmacodynamics
BZP promotes monoamine release by acting on serotonin, norepinephrine, and dopamine transporters, with the strongest reported releasing activity at the norepinephrine transporter and lower potency at the dopamine and serotonin transporters. It also antagonizes alpha-2 adrenergic receptors, which can reduce presynaptic negative feedback and increase norepinephrine release. BZP acts as a non-selective serotonin receptor agonist; activity at 5-HT2A may contribute to high-dose hallucinogenic effects, while reported partial agonist or antagonist activity at 5-HT2B remains less certain.
Pharmacokinetics
Absorption & half-lifenot documented yetMetabolitesnone documented yet
Interactions
Interactions not written up yet
An unlisted combination is an unknown one, not a safe one. Check a dedicated combination chart before mixing.
Tolerance
Tolerance timelines are rules of thumb, not exact schedules, and vary widely between individuals and use patterns.
One anecdotal internet report described tolerance becoming noticeable after 5–8 days of daily BZP use1. Research is sparse, and the reports do not specify a timeframe or use pattern.
Harm Potential
Addiction & Dependence
Psychological
ModerateBZP has amphetamine-like effects and was identified as liable to abuse during early research. Studies indicate it can substitute for methamphetamine in addicted animals, though it is approximately one-tenth as potent and produces correspondingly weaker addictive effects.
Toxicity
Deaths from BZP alone are extremely rare, but at least one fatality has been attributed to BZP ingestion alone with a measured blood concentration of 8 mg/L. Multiple deaths have been reported when BZP was combined with alcohol, TFMPP, or MDMA.
Renal toxicity has been reported as an adverse effect following BZP use, though specific conditions predisposing to this outcome are not well characterized.
BZP can cause unpredictable and serious toxicity in some individuals, including life-threatening seizures with status epilepticus; fourteen toxic seizures were recorded in two patients who also developed severe respiratory and metabolic acidosis.
Respiratory failure has been reported among the more severe toxic effects of BZP use.
Rhabdomyolysis has been reported as a severe toxic effect of BZP use.
Psychosis Risk
Acute psychosis and adverse psychiatric events have been reported following BZP use. Hallucinations, confusion, agitation, and anxiety are among the documented side effects.
Seizure Risk
Seizures are a documented serious adverse effect of BZP. Life-threatening toxicity with status epilepticus has been recorded, with fourteen toxic seizures observed in two patients who also developed severe respiratory and metabolic acidosis. BZP can cause unpredictable and serious toxicity in some individuals.
History & Culture
Development and early investigations
BZP was first synthesized by Burroughs Wellcome & Company in 1944. Early piperazine research focused largely on potential antihelminthic uses, but BZP was largely abandoned as a worm treatment after side effects were identified. In the 1970s, it was investigated as a possible antidepressant before
Legality
International
Controlled internationally under the UN Convention on Psychotropic Substances 1971.
By Country
Illegal6
United StatesIllegalUnder federal law, N-Benzylpiperazine (BZP) is listed as a Schedule I stimulant in 21 C.F.R. § 1308.11(f)(3), with permanent placement effective March 18, 2004. The listing covers any quantity in a material, compound, mixture, or preparation, including its salts, isomers, and salts of isomers. Except as authorized by the Controlled Substances Act, knowing or intentional manufacture, distribution, dispensing, possession with intent to undertake those acts, and simple possession are unlawful; simple possession also has statutory exceptions for a substance obtained directly or under a valid prescription or order from a practitioner acting in professional practice.
AustraliaIllegalBenzylpiperazine (BZP) is listed by exact name in Schedule 9 of the Therapeutic Goods (Poisons Standard—June 2026) Instrument 2026. Schedule 9 covers substances whose manufacture, possession, supply or use should be prohibited by law, subject to approved medical or scientific research and analytical, teaching or training purposes; its classifications are implemented through State and Territory legislation. The Criminal Code Regulations 2019 also list benzylpiperazine as a controlled drug, and section 308.1 of the Commonwealth Criminal Code makes possession punishable by imprisonment for 2 years, 400 penalty units, or both.
CanadaIllegalBenzylpiperazine (BZP), namely 1-benzylpiperazine and its salts, isomers, and salts of isomers, is listed in Schedule III, item 33 of the Controlled Drugs and Substances Act. The listing took effect on 30 March 2012. The Act prohibits unauthorized possession, trafficking, possession for trafficking, import, export, and production of Schedule III substances, subject to statutory and regulatory authorizations and exceptions.
FinlandIllegalValtioneuvoston asetus huumausaineina pidettävistä aineista, valmisteista ja kasveista (543/2008), liite II1112131415
BZP is listed as N-bentsyylipiperatsiini (BZP), chemically identified as 1-bentsyyli-1,4-diatsasykloheksaani, in List II of Annex II to Decree 543/2008 and is therefore classified as a narcotic drug. Its production, manufacture, import, export, transport, transit, distribution, trade, handling, possession, and use are prohibited, subject to statutory exceptions for medical, research, and control purposes. BZP has been expressly controlled under the decree since 1 September 2008, and the operative Annex II retained it when replaced with effect from 25 April 2025.
New ZealandIllegalBZP is listed by exact name in Schedule 3 Part 1 clause 2 of the Misuse of Drugs Act 1975 as a Class C controlled drug. The classification took effect on 1 April 2008; possession, use, supply, and administration are controlled subject to licences, regulations, exemptions, and statutory defences.
United KingdomIllegal1-Benzylpiperazine (BZP) is named in Schedule 2 Part III paragraph 1(ca) of the Misuse of Drugs Act 1971 and has been a Class C controlled drug since 23 December 2009. The Act restricts possession, possession with intent to supply, production, supply, offering to supply, import, and export, subject to applicable regulations, licences, exceptions, and statutory defences.
References
Source Pages
Citations
Further Reading
Antia et al. 2009 - Pharmacokinetics of BZP- Baumann et al. 2005 - N-substituted piperazines mimic MDMA
DrugWise: BZP Profile
EUDA: Drug Profile - BZP/Piperazines
Lin et al. 2011 - Subjective effects of BZP and TFMPP- Schep et al. 2011 - Clinical toxicology of BZP and TFMPP
- Arbo et al. 2012 - Piperazine compounds as drugs of abuse
- Wood et al. 2008 - Dissociative and sympathomimetic toxicity associated with recreational use of 1-(3-trifluoromethylphenyl) piperazine (TFMPP) and 1-benzylpiperzine (BZP)
- Baumann et al. 2004 - N-Substituted Piperazines Abused by Humans Mimic the Molecular Mechanism of 3,4-Methylenedioxymethamphetamine (MDMA, or ‘Ecstasy’)
Article Status
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