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4-FPP

This article is a stubmissing:
Subjective Effects
Interactions
Tolerance
Legality
4-FPP molecule structure4-FPP molecule structure
4-Fluorophenylpiperazine
pFPP, Fluoperazine, Flipiperazine, para-FluorophenylpiperazineOpen in Piru
Psychoactive Class
Stimulant (mild)Entactogen
Chemical Class
PiperazinePhenylpiperazine

4-FPP is a phenylpiperazine1 with mild stimulant effects2 and reported psychedelic, euphoric, and entactogenic qualities. It was first identified in 1982 as a metabolite of the hypnotic drug niaprazine1 and was rediscovered in 2003 as a potential recreational drug.3 It has been sold in recreational “party pills,”3 initially in New Zealand, and has also been found in illicit pills sold as ecstasy. Higher doses can cause migraine headaches, muscle aches, anxiety, nausea, and vomiting.2

Dosage & Duration

Log in Piru

Dosage

Doses are population estimates that vary widely between individuals.

Threshold~20 mg
Light20-40 mg
Moderate40-80 mg
Strong80-150 mg
Heavy150+ mg

Duration

Onset15-45 minutes
Total4-8 hours

Subjective Effects

Subjective Effects not written up yet

Pharmacology

Pharmacodynamics

In vitro, 4-FPP acts mainly as a 5-HT1A receptor agonist. It also binds to 5-HT2A and 5-HT2C receptors and inhibits serotonin and norepinephrine reuptake. It may additionally promote the release of serotonin and norepinephrine.

Pharmacokinetics

Metabolic studies show that 4-FPP inhibits several cytochrome P450 enzymes in the liver.

Metabolitesnone 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.

Check TripSit

Tolerance

Tolerance not written up yet

Harm Potential

Toxicity

Hepatic

Inhibition of various Cytochrome P450 enzymes in the liver has been demonstrated, which may contribute to the substance's side-effect profile and potential for drug interactions.

Central Nervous System

Higher doses above the typical active range can cause migraine headaches and anxiety.

Musculoskeletal

Muscle aches have been reported at higher doses.

Gastrointestinal

Nausea and vomiting can occur at higher doses.

History & Culture

4-FPP was first discovered in 1982 as a metabolite of niaprazine.5 In 2003, it was rediscovered as a potential recreational drug.…

Legality

Legality not written up yet

References

Source Pages

  1. Erowid: 4-FPP Experience Vault
  2. Wikipedia

Citations

  1. An Overview of New Psychoactive Substances and the Outlets Supplying Them. National Advisory Committee on Drugs (2011). https://www.drugsandalcohol.ie/15390/2/NACDoverview3B217396d01.pdf12
  2. Piperazine Based Substances of Abuse: A new Party Pills on Bulgarian Drug Market. Biotechnology & Biotechnological Equipment (2008). https://doi.org/10.1080/13102818.2008.1081752912
  3. Qualitative research of online drug misuse communities with reference to the novel psychoactive substances. University of Hertfordshire (2012). https://uhra.herts.ac.uk/id/eprint/16516/1/08196683%20Jebadurai%20Jeshoor%20final%20MD%20submission.pdf12
  4. The piperazine analogue para-fluorophenylpiperazine alters timing of the physiological effects of the synthetic cannabinoid receptor agonist AMB-FUBINACA, without changing its discriminative stimulus, signalling effects, or metabolism. RTI International (2023). https://doi.org/10.1016/j.pbb.2023.1735301
  5. An Overview of New Psychoactive Substances and the Outlets Supplying Them. National Advisory Committee on Drugs (2011). https://www.drugs.ie/resourcesfiles/ResearchDocs/Ireland/2011/Head_Report2011_overview.pdf1
  6. Item 6: BZP Update. Expert Advisory Committee on Drugs (n.d.). https://fyi.org.nz/request/13899/response/52670/attach/5/2.Item%206.BZP%20Update.pdf1

Further Reading

  1. Antia U et al. - Interaction potential of party-pill piperazines with CYP450
  2. Antia U et al. Interaction potential of party-pill piperazines with CYP450.
  3. Arbo et al. - Piperazine compounds as drugs of abuse (Review)
  4. EMCDDA: 4-Fluorophenylpiperazine profile
  5. Nichols DE et al. - Serotonergic pharmacology of phenylpiperazines
  6. Nichols DE et al. Serotonergic pharmacology of p-fluorophenylpiperazine.
  7. Scherman D et al. - Molecular pharmacology of niaprazine and its metabolites
  8. Scherman D et al. Molecular pharmacology of niaprazine and its metabolites.
  9. Staack RF & Maurer HH - Metabolism of designer piperazines
  10. Staack RF & Maurer HH. Metabolism of designer piperazines.

Article Status

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    Step 1 · Automated synthesis

    An autonomous workflow built by Josie Kins compiled this article's foundation from information published across the web.

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    Not yet reviewed: this article is pending editorial review by Lyrea.

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