MDMB-4en-PINACA, often erroneously referred to as 5-CL-ADB-A, is an indazole-based synthetic cannabinoid that has gained popularity as an online designer drug. In 2021, the Drug Enforcement Administration (DEA) in the United States reported MDMB-4en-PINACA as the most prevalent synthetic cannabinoid in circulation.[8] Notably, MDMB-4en-PINACA distinguishes itself from 5F-MDMB-PINACA by substituting the 5-fluorophenyl group with a pent-4-ene moiety (4-en).

IUPAC name
CAS Number2504100-70-1 
PubChem CID155804661
Chemical and physical data
Molar mass357.454 g·mol−1

Legal status

On December 18, 2019, Sweden’s public health agency recommended the classification of MDMB-4en-PINACA as a hazardous substance.
In the United States, the DEA has issued a notice of its intent to provisionally categorize MDMB-4en-PINACA as a Schedule I controlled substance, with an effective date on or after May 4, 2023, lasting for up to 2 years. During this period, the DEA may pursue permanent scheduling. If filed on May 4, 2023, and endless scheduling is not followed, the temporary Schedule I designation will expire on May 4, 2025.
As of April 27, 2023, North Dakota has already designated MDMB-4en-PINACA as a Schedule I controlled substance.


  • What is MDMB-4en-PINACA?
  • MDMB-4en-PINACA is a synthetic cannabinoid that has gained attention as a designer drug. It belongs to a class of chemicals designed to mimic the effects of cannabinoids found in the cannabis plant.
  • Is MDMB-4en-PINACA Legal?
  • The legal status of MDMB-4en-PINACA varies by jurisdiction. In some places, it may be classified as a controlled substance, while in others, it may not have a specific legal status.
  • What Are the Effects of MDMB-4en-PINACA?
  • The effects of MDMB-4en-PINACA can include relaxation, altered perception, and increased heart rate. However, it can also lead to anxiety, paranoia, and other adverse effects.
  • Is MDMB-4en-PINACA Safe to Use?
  • The safety of using MDMB-4en-PINACA needs to be well-documented, and it may pose health risks. The lack of research and regulation means the purity and safety of products containing this substance can vary.
  • How is MDMB-4en-PINACA Consumed?
  • MDMB-4en-PINACA is typically inhaled as a vapour, but it can also be ingested or used in other ways. The method of use and dosage can significantly impact the potential risks and effects.
  • Is MDMB-4en-PINACA Addictive?
  • Synthetic cannabinoids like MDMB-4en-PINACA can be habit-forming, and some individuals have reported withdrawal symptoms when discontinuing use. The potential for addiction varies from person to person.
  • Can MDMB-4en-PINACA Be Detected in Drug Tests?
  • MDMB-4en-PINACA and similar synthetic cannabinoids might not be detected in standard drug tests. However, some specialized tests can identify their presence.
  • Are There Health Risks Associated with MDMB-4en-PINACA?
  • Yes, there are health risks associated with MDMB-4en-PINACA use. These risks may include cardiovascular problems, anxiety, paranoia, and adverse psychological effects. The lack of quality control in illicit products makes it difficult to predict the exact risks.
  • Can MDMB-4en-PINACA be used for Medical Purposes?
  • MDMB-4en-PINACA is not approved for medical use nor considered a safe or effective treatment for any medical condition. It is strictly intended for research purposes.
  • Where Can I Get Help or More Information About MDMB-4en-PINACA?
  • If you have concerns about MDMB-4en-PINACA or need assistance with substance abuse, seek help from a medical professional, addiction specialist, or helpline. Additionally, reliable sources like government health agencies can provide information on the potential risks associated with this substance.


  1. Anvisa (2023-07-24) – “RDC Nº 804 – Listas de Substâncias Entorpecentes, Psicotrópicas, Precursoras e Outras sob Controle Especial” [Collegiate Board Resolution No. 804 – Lists of Narcotic, Psychotropic, Precursor, and Other Substances under Special Control] (in Brazilian Portuguese). Published in Diário Oficial da União on 2023-07-25. Archived from the original on 2023-08-27. Retrieved on 2023-08-27.
  2. Watanabe S, Vikingsson S, Åstrand A, Gréen H, Kronstrand R (December 2019) – “Biotransformation of the New Synthetic Cannabinoid with an Alkene, MDMB-4en-PINACA, by Human Hepatocytes, Human Liver Microsomes, and Human Urine and Blood.” Published in The AAPS Journal, Volume 22, Issue 1, Page 13. DOI: 10.1208/s12248-019-0381-3. PMID: 31848852. S2CID: 209393242.
  3. “MDMB-4en-PINACA” – Available at
  4. Erol Ozturk Y, Yeter O (January 2021) – “In Vitro Phase I Metabolism of the Recently Emerged Synthetic MDMB-4en-PINACA and Its Detection in Human Urine Samples.” Published in the Journal of Analytical Toxicology, Volume 44, Issue 9, Pages 976–984. DOI: 10.1093/jat/bkaa017. PMID: 32091101.
  5. Wang Y, Pan Y, Yang H, Liu J, Wurita A, Hasegawa K (July 2022) – “Quantification of MDMB-4en-PINACA and ADB-BUTINACA in human hair by gas chromatography-tandem mass spectrometry.” Published in Forensic Toxicology, Volume 40, Issue 2, Pages 340–348. DOI: 10.1007/s11419-022-00615-z. PMID: 36454410. S2CID: 247501663.
  6. Wagmann L, Stiller RG, Fischmann S, Westphal F, Meyer MR (October 2022) – “Going deeper into the toxicokinetics of synthetic cannabinoids: in vitro contribution of human carboxylesterases.” Published in Archives of Toxicology, Volume 96, Issue 10, Pages 2755–2766. DOI: 10.1007/s00204-022-03332-z. PMC: 9352624. PMID: 35788413. S2CID: 250281976.
  7. Giorgetti A, Brunetti P, Pelotti S, Auwärter V (October 2022) – “Detection of AP-237 and synthetic cannabinoids on an infused letter sent to a German prisoner.” Published in Drug Testing and Analysis, Volume 14, Issue 10, Pages 1779–1784. DOI: 10.1002/dta.3351. PMC: 9804899. PMID: 35918775. S2CID: 251281159.
  8. “Emerging Threat Report” (PDF) – Published by the Drug Enforcement Administration in 2021.
  9. “ANALYTICAL REPORT MDMB-PINACA N1-pentyl-4-en isomer” (PDF) – Available at
  10. Krotulski AJ, Cannaert A, Stove C, Logan BK (February 2021) – “The next generation of synthetic cannabinoids: Detection, activity, and potential toxicity of pent-4en and but-3en analogues including MDMB-4en-PINACA.” Published in Drug Testing and Analysis, Volume 13, Issue 2, Pages 427–438. DOI: 10.1002/dta.2935. PMID: 32997377. S2CID: 222148050.
  11. Cannaert A, Sparkes E, Pike E, Luo JL, Fang A, Kevin RC, et al. (December 2020) – “Synthesis and in Vitro Cannabinoid Receptor 1 Activity of Recently Detected Synthetic Cannabinoids.” Published in ACS Chemical Neuroscience, Volume 11, Issue 24, Pages 4434–4446. DOI: 10.1021/acschemneuro.0c00644. PMID: 33253529. S2CID: 227246346.
  12. Pike E, Grafinger KE, Cannaert A, Ametovski A, Luo JL, Sparkes E, et al. (July 2021) – “Systematic evaluation of a panel of 30 synthetic cannabinoid receptor agonists structurally related to MMB-4en-PICA, MDMB-4en-PINACA, ADB-4en-PINACA, and MMB-4CN-BUTINACA using a combination of binding and different CB1 receptor activation assays: Part I.” Published in Drug Testing and Analysis, Volume 13, Issue 7, Pages 1383–1401. DOI: 10.1002/dta.3037. PMID: 33787091.
  13. Grafinger KE, Cannaert A, Ametovski A, Sparkes E, Cairns E, Banister SD, et al. (July 2021) – “Systematic evaluation of a panel of 30 synthetic cannabinoid receptor agonists structurally related to MMB-4en-PICA, MDMB-4en-PINACA, ADB-4en-PINACA, and MMB-4CN-BUTINACA using a combination of binding and different CB1 receptor activation assays-Part II.” Published in Drug Testing and Analysis, Volume 13, Issue 7, Pages 1402–1411. DOI: 10.1002/dta.3035. PMID: 33769699.
  14. “Tjugotre ämnen föreslås klassas som narkotika eller hälsofarlig vara” [Twenty-three substances are proposed to be classified as narcotics or health hazards]. Published by Folkhälsomyndigheten [The Public Health Authority] (in Swedish) on 18 December 2019. Archived from the original on 19 December 2019.
  15. “Federal Register :: Request Access.”
  16. “AN ACT to amend and reenact sections 19-03.1-05, 19-03.1-11, and 19-03.1-13 of the North Dakota Century Code, relating to the scheduling of controlled substances; and to declare an emergency” (PDF). Published by the Sixty-eighth Legislative Assembly of North Dakota in Regular Session on 3 January 2023.

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