white → yellow2 → brown2
Not yet reviewed — this article is pending editorial review by Lyrea.
JWH-018
1-Pentyl-3-(1-naphthoyl)indole
AM-678, Spice (component)
JWH-018 is a synthetic cannabinoid of the naphthoylindole class.12 It gained widespread recognition from 2006 onward as the primary active ingredient in "Spice" brand herbal smoking blends, which were marketed as potpourri and labeled "not for human consumption." The Spice brand became so dominant that the name was eventually adopted as a generic term for all synthetic cannabinoids. JWH-018 produces cannabis-like effects when smoked but carries the heightened risks characteristic of synthetic cannabinoid compounds.
Dosage & Duration
Dosage
Light1-2 mg
Moderate2+ mg
Dosing information for smoked JWH-018 derives primarily from oral administration reports and animal research rather than controlled human inhalation studies. Threshold effects have been observed at sub-milligram quantities, though an exact threshold dose has not been determined in published literature. As with other synthetic cannabinoids, considerable variation in potency has been documented across different batches and synthesis methods.
Duration
Onset30 seconds
Total2 hours
Half-life
~1.69 hours (median)
Subjective Effects
Effects vary widely by individual, dose, and context.
Physical
Perception of increased weight or Perception of decreased weight
Cognitive
Visual
Auditory
Pharmacology
Pharmacodynamics
JWH-018 acts as a full agonist at both the CB1 and CB2 cannabinoid receptors, with some selectivity for CB2.3 It displays binding affinities of 9.00 ± 5.00 nM at CB1 and 2.94 ± 2.65 nM at CB2, with its CB1 affinity reported as approximately five times greater than that of THC.3 Unlike THC, which acts as a partial agonist at CB1, JWH-018's full agonist activity produces more complete receptor activation.4
Pharmacokinetics
JWH-018 undergoes extensive metabolism primarily through hydroxylation and N-dealkylation.5 In humans, metabolism occurs mainly on the indole ring and pentyl side chain, with the resulting hydroxylated metabolites undergoing extensive glucuronide conjugation.5 The parent compound and its N-dealkylated metabolite are detected only in small quantities in urine, while hydroxylated N-dealkylated metabolites constitute the primary urinary signal.6 When inhaled, the median elimination half-life is approximately 1.69 hours.7
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
Full Tolerance
Tolerance develops with repeated use, involving CB1 receptor desensitization. Animal studies demonstrate that chronic administration leads to significant downregulation of CB1 receptor function.
Cross Tolerance
Cannabinoids (including THC and other synthetic cannabinoid receptor agonists)
Harm Potential
Addiction & Dependence
Psychological
ModerateAt least one case of JWH-018 dependence has been reported following daily use over eight months.8 As a full CB1 agonist with indirect dopaminergic activity, JWH-018 may have greater reinforcing potential than cannabis, though individual susceptibility varies.9
Physical
LowWithdrawal symptoms have been reported following prolonged daily use and were described as more severe than those experienced from cannabis dependence.10
Psychosis Risk
May cause intense anxiety and agitation. Psychotic relapses and anxiety symptoms have been reported in patients with pre-existing mental illness following inhalation.11 Due to concerns about psychosis induction in vulnerable individuals, it is recommended that people with risk factors for psychotic disorders, such as a past or family history of psychosis, not use synthetic cannabinoids.11
Seizure Risk
Seizures and convulsions have been reported in rare cases, though causation has not been definitively established.12
History & Culture
Legality
By Country
United StatesIllegalSchedule I
CanadaIllegalSchedule II
Controlled Drugs and Substances Act19
JWH-018 is included in Schedule II to the Controlled Drugs and Substances Act as a synthetic cannabinoid receptor type 1 agonist. The schedule expressly identifies 1-pentyl-3-(1-naphthoyl)indole as JWH-018, and the Act prohibits unauthorized possession, trafficking, importation, exportation, and production of Schedule II substances.
FinlandIllegalJWH-018
Valtioneuvoston asetus huumausaineina pidettävistä aineista, valmisteista ja kasveista (543/2008)21
Finland’s Government Decree 543/2008 expressly lists JWH-018 with its chemical name, 1-pentyyli-3-(1-naftoyyli)indoli. Section 1 provides that the substances, preparations and plants in annexes I–V are regarded as narcotics, placing JWH-018 within Finland’s narcotics-control regime.
NetherlandsIllegalLijst I
Opiumwet23
JWH-018 is expressly listed on List I of the Dutch Opium Act, with the chemical description naphthaleen-1-yl(1-pentyl-1H-indol-3-yl)methanon. Article 2 prohibits importing or exporting, preparing, processing, selling, supplying, transporting, possessing, and manufacturing List I substances. The Act also places synthetic cannabinoids within a separate generic substance-group regime on List IA, but JWH-018 is specifically scheduled on List I.
PolandIllegalGroup II-P
Rozporządzenie Ministra Zdrowia z dnia 17 sierpnia 2018 r. w sprawie wykazu substancji psychotropowych, środków odurzających oraz nowych substancji psychoaktywnych (Dz. U. 2024 poz. 1139), as amended by Dz. U. 2025 poz. 598 and Dz. U. 2026 poz. 934252627
JWH-018 is expressly listed in Group II-P with the exact chemical designation naftalen-1-ylo(1-pentyloindol-3-ilo)metanon. The official 2025 amendment changes Group II-P item 76 and adds items 79–82; the official 2026 amendment adds items 83–85. Neither changes or repeals item 59. The 2026 amendment entered into force 14 days after its 13 July 2026 publication.
SwedenIllegalJWH-018
Förordning (1992:1554) om kontroll av narkotika, bilaga 129
Sweden’s official Annex 1 lists JWH-018 under the chemical name Naphthalene-1-yl-(1-pentylindol-3-yl)methanon. Section 2 of Förordning (1992:1554) provides that substances in the annex are narcotics under the Narcotics Penal Law, so JWH-018 is prohibited outside the statutory control regime.
UkraineIllegalTable I · List 2
Cabinet of Ministers Resolution No. 770 of 6 May 2000, List of Narcotic Drugs, Psychotropic Substances and Precursors32
Ukraine expressly lists JWH-018, with the chemical name (naphthalen-1-yl)(1-pentyl-1H-indol-3-yl)methanone, in Table I, List No. 2. That list is headed ‘particularly dangerous psychotropic substances, circulation of which is prohibited’; its note also covers derivatives of the naphthoylindole group.
AustriaIllegalAnhang IV.1
Suchtgiftverordnung18
JWH-018 is listed in Anhang IV.1 of the Suchtgiftverordnung. The annex places it among substances and preparations in Annex II of the United Nations Convention on Psychotropic Substances.
DenmarkIllegalJWH-018
Bekendtgørelse om euforiserende stoffer (BEK nr 405 af 26/03/2026), liste B20
Denmark’s List B expressly names JWH-018 and gives its chemical name as naphthalen-1-yl-(1-pentylindol-3-yl)methanon. The Order prohibits possession, import, export, sale, purchase, supply, receipt, manufacture, and processing of List B euphoriant substances except as authorized under the Order; it also covers salts and simple psychoactive derivatives, such as esters and ethers.
GermanyIllegalAnlage II
Betäubungsmittelgesetz22
JWH-018 is listed in Anlage II to the Betäubungsmittelgesetz. The schedule identifies it as 1-pentyl-3-(1-naphthoyl)indole and gives the corresponding chemical name.
NorwayIllegalForbudt etter § 5
Forskrift om narkotika (narkotikaforskriften), FOR-2013-02-14-199, narkotikalisten and § 524
Norway's current narkotikalisten directly lists JWH-018 and gives its chemical designation as naftalen-1-yl(1-pentyl-1H-indol-3-yl)metanon. Its inclusion in the official narcotics list places JWH-018 under the regulation's prohibition in § 5; this is direct named coverage, not analogue coverage.
SingaporeIllegalClass A controlled drug
Misuse of Drugs Act 1973, First Schedule (Class A Drugs)28
JWH-018 is listed by its chemical name in the First Schedule's Class A Drugs. The listing sits within a structural category that expressly includes salts, stereoisomers, and preparations or products containing the covered compounds.
ThailandRestrictedCategory I
Narcotics Code, sections 23, 30 and 35; Table of Controlled Psychotropic Substances under the Narcotics Code (Thai FDA update 25 July 2025)3031
The Thai FDA's table updated 25 July 2025 expressly lists JWH-018 in Category I. Under section 30 of the Narcotics Code, Category I covers psychotropic substances not used medically and with high actual or potential misuse; section 35 provides that the licensing authority may license production, import, export, sale, possession, or transit of psychotropic substances. This supports a controlled/restricted classification rather than the refuted claim that Category I itself means prohibited.
United KingdomIllegalClass B
Misuse of Drugs Act 1971, Schedule 2, Part II33
Classified under the Misuse of Drugs Act at the end of 2009.34 JWH-018 was among the first synthetic cannabinoids to be formally controlled in the UK, prompted by its widespread availability in products marketed as 'Spice' or herbal incense.
References
Source Pages
Citations
- Liana Fattore, & Walter Fratta. (2011). Beyond THC: The New Generation of Cannabinoid Designer Drugs. https://doi.org/10.3389/fnbeh.2011.000601
- Detection and disposition of JWH-018 and JWH-073 in mice after exposure to "Magic Gold" smoke. (2012). https://doi.org/10.1016/j.forsciint.2012.02.0031
- JWH018, a common constituent of 'Spice' herbal blends, is a potent and efficacious cannabinoid CB receptor agonist. British Journal of Pharmacology, 160(3), 585–593 (June 2010). https://doi.org/10.1111/j.1476-5381.2009.00582.x12
- Evaluation of first generation synthetic cannabinoids on binding at non-cannabinoid receptors and in a battery of in vivo assays in mice. (n.d.). https://pmc.ncbi.nlm.nih.gov/articles/PMC5028280/1
- Tim Sobolevsky, Ilya Prasolov, & Grigory Rodchenkov. (July 2010). Detection of JWH-018 metabolites in smoking mixture post-administration urine. Forensic Science International, 200(1–3), 141–7. https://doi.org/10.1016/j.forsciint.2010.04.00312
- Cindy L. Moran, Vi-Huyen Le, Krishna C. Chimalakonda, Amy L. Smedley, Felisia D. Lackey, Suzanne N. Owen, Paul D. Kennedy, Gregory W. Endres, Fred L. Ciske, James B. Kramer, Andrei M. Kornilov, L. D. Bratton, Paul J. Dobrowolski, William D. Wessinger, William E. Fantegrossi, Paul L. Prather, Laura P. James, Anna Radominska-Pandya, & Jeffery H. Moran. (June 2011). Quantitative measurement of JWH-018 and JWH-073 metabolites excreted in human urine. Anal. Chem., 83(11), 4228–36. https://doi.org/10.1021/ac20056361
- Stefan W. Toennes, Anna Geraths, Werner Pogoda, Alexander Paulke, Cora Wunder, Eef L. Theunissen, & Johannes G. Ramaekers. (April 2018). Pharmacokinetic properties of the synthetic cannabinoid JWH-018 in oral fluid after inhalation. Drug Testing and Analysis, 10(4), 644–650. https://doi.org/10.1002/dta.231012
- Ulrich S. Zimmermann, Patricia R. Winkelmann, Max Pilhatsch, Josef A. Nees, Rainer Spanagel, & Katja Schulz. (2009). Withdrawal Phenomena and Dependence Syndrome After the Consumption of "Spice Gold". Dtsch Ärztebl Int, 106(27), 464–467. https://doi.org/10.3238/arztebl.2009.04641
- Stimulation of in vivo dopamine transmission and intravenous self-administration in rats and mice by JWH-018, a Spice cannabinoid. (n.d.). https://pubmed.ncbi.nlm.nih.gov/26327678/1
- Every-Palmer S, Nowitz M, Grant E, Brandt L, & Bhatt M. (2022). Clinical withdrawal symptom profile of synthetic cannabinoid receptor agonists and comparison of effects with high potency cannabis. 239, 1083–1094. https://doi.org/10.1007/s00213-021-05768-01
- Susanna Every-Palmer. (September 2011). Synthetic cannabinoid JWH-018 and psychosis: an explorative study. Drug and Alcohol Dependence, 117(2–3), 152–157. https://doi.org/10.1016/j.drugalcdep.2011.01.01212
- Lapoint J, James LP, Moran CL, Nelson LS, Hoffman RS, & Moran JH. (2011). Convulsions Associated with the Use of a Synthetic Cannabinoid Product. 7(3), 213–219. https://doi.org/10.1007/s13181-011-0182-21
- Huffman, John W.. (2005). Synthesis of Cannabinoid Receptor Ligands — NIH NIDA grant K05-DA015340. National Institute on Drug Abuse / Grantome. https://grantome.com/grant/NIH/K05-DA015340-031
- The Unlikely Clemson Chemist Behind Synthetic Marijuana. (n.d.). https://www.wfae.org/local-news/2011-01-25/the-unlikely-clemson-chemist-behind-synthetic-marijuana1
- European Monitoring Centre for Drugs and Drug Addiction.. (2009). Understanding the Spice Phenomenon. European Monitoring Centre for Drugs and Drug Addiction.. https://doi.org/10.2810/2706312
- Seely, K.A., Lapoint, J., Moran, J.H., Uchiyama, N., Kikura-Hanajiri, R., & Goda, Y.. (2014). Spice/K2 drugs — more than innocent substitutes for marijuana. International Journal of Neuropsychopharmacology, 17(3), 509-519. https://doi.org/10.1017/s146114571300158212
- Rainer Lindigkeit, Anja Boehme, Ina Eiserloh, Maike Luebbecke, Marion Wiggermann, Ludger Ernst, & Till Beuerle. (2009). Spice: A never ending story?. Forensic Science International, 191(1), 58–63. https://doi.org/10.1016/j.forsciint.2009.06.00812
- Suchtgiftverordnung. ris.bka.gv.at (n.d.). https://ris.bka.gv.at/NormDokument.wxe?Abfrage=Bundesnormen&Anlage=4&Artikel=&Gesetzesnummer=10011053&Paragraf=&ShowPrintPreview=True&Uebergangsrecht=1
- Controlled Drugs and Substances Act. laws-lois.justice.gc.ca (n.d.). https://laws-lois.justice.gc.ca/eng/acts/C-38.8/FullText.html1
- Bekendtgørelse om euforiserende stoffer (BEK nr 405 af 26/03/2026), liste B. retsinformation.dk (n.d.). https://www.retsinformation.dk/api/pdf/2559321
- Valtioneuvoston asetus huumausaineina pidettävistä aineista, valmisteista ja kasveista (543/2008). finlex.fi (n.d.). https://www.finlex.fi/fi/lainsaadanto/2008/5431
- Betäubungsmittelgesetz. gesetze-im-internet.de (n.d.). https://www.gesetze-im-internet.de/btmg_1981/anlage_ii.html1
- Opiumwet. wetten.overheid.nl (n.d.). https://wetten.overheid.nl/BWBR0001941/2026-01-011
- Forskrift om narkotika (narkotikaforskriften), narkotikalisten. lovdata.no (n.d.). https://lovdata.no/dokument/SF/forskrift/2013-02-14-199/KAPITTEL_1-11
- Rozporządzenie Ministra Zdrowia z dnia 17 sierpnia 2018 r. w sprawie wykazu substancji psychotropowych, środków odurzających oraz nowych substancji psychoaktywnych (Dz. U. 2024 poz. 1139), as amended by Dz. U. 2025 poz. 598 and Dz. U. 2026 poz. 934. eli.gov.pl (n.d.). https://eli.gov.pl/api/acts/DU/2024/1139/text.html1
- Rozporządzenie Ministra Zdrowia z dnia 17 sierpnia 2018 r. w sprawie wykazu substancji psychotropowych, środków odurzających oraz nowych substancji psychoaktywnych (Dz. U. 2024 poz. 1139), as amended by Dz. U. 2025 poz. 598 and Dz. U. 2026 poz. 934. eli.gov.pl (n.d.). https://eli.gov.pl/api/acts/DU/2025/598/text.pdf1
- Rozporządzenie Ministra Zdrowia z dnia 17 sierpnia 2018 r. w sprawie wykazu substancji psychotropowych, środków odurzających oraz nowych substancji psychoaktywnych (Dz. U. 2024 poz. 1139), as amended by Dz. U. 2025 poz. 598 and Dz. U. 2026 poz. 934. eli.gov.pl (n.d.). https://eli.gov.pl/api/acts/DU/2026/934/text.pdf1
- Misuse of Drugs Act 1973, First Schedule (Class A Drugs). sso.agc.gov.sg (n.d.). https://sso.agc.gov.sg/Act/MDA1973?Phrase=JWH-018&ProvIds=Sc1-&ViewType=Within&WiAl=11
- Förordning (1992:1554) om kontroll av narkotika, bilaga 1. riksdagen.se (n.d.). https://www.riksdagen.se/sv/dokument-lagar/dokument/svensk-forfattningssamling/forordning-19921554-om-kontroll-av-narkotika_sfs-1992-15541
- Narcotics Code, sections 23, 30 and 35; Table of Controlled Psychotropic Substances under the Narcotics Code (Thai FDA update 25 July 2025). narcotic.fda.moph.go.th (n.d.). https://narcotic.fda.moph.go.th/media.php?id=790834351574228992&name=PHYCHO%20list%20%28update%2025.07.2025%29.pdf1
- Narcotics Code, sections 23, 30 and 35; Table of Controlled Psychotropic Substances under the Narcotics Code (Thai FDA update 25 July 2025). narcotic.fda.moph.go.th (n.d.). https://narcotic.fda.moph.go.th/media.php?id=498847832757903360&name=NA_10~1.PDF1
- Cabinet of Ministers Resolution No. 770 of 6 May 2000, List of Narcotic Drugs, Psychotropic Substances and Precursors. zakon.rada.gov.ua (n.d.). https://zakon.rada.gov.ua/laws/show/770-2000-%D0%BF1
- Misuse of Drugs Act 1971, Schedule 2, Part II. legislation.gov.uk (n.d.). https://www.legislation.gov.uk/ukpga/1971/38/schedule/21
- The Misuse of Drugs Act 1971 (Amendment) Order 2009. (n.d.). https://www.legislation.gov.uk/uksi/2009/3209/made1
- Controlled Substances Act, 21 U.S.C. § 812(c), Schedule I(d). uscode.house.gov (n.d.). https://uscode.house.gov/view.xhtml?req=(title:21%20section:812)&f=treesort&num=0&edition=prelim1
- Controlled Substances Act, 21 U.S.C. § 812(c), Schedule I(d). ecfr.gov (n.d.). https://www.ecfr.gov/current/title-21/chapter-II/part-1308/section-1308.111
- Synthetic Drug Abuse Prevention Act of 2012 (SDAPA) — Title XI, Subtitle D of the Food and Drug Administration Safety and Innovation Act (P.L. 112-144). (n.d.). https://www.congress.gov/bill/112th-congress/senate-bill/3190/text1
- Schedules of Controlled Substances: Temporary Placement of Five Synthetic Cannabinoids Into Schedule I — Federal Register Vol. 76 No. 40 (March 1, 2011). (n.d.). https://www.govinfo.gov/content/pkg/FR-2011-03-01/html/2011-4428.htm1
Further Reading
Brents et al. (2011) - Phase I Metabolites Activity
CYP2C9 polymorphism metabolism- Freeman et al. (2013) - Stroke Association
- Grigoryev et al. (2022) - Psychotomimetic Effects Study
- Human Inhalation Pharmacokinetics (2–3 mg)
- Human inhalation PK (2–3 mg)
- JWH-018 Phase 1 Pilot Study
- Koller et al. (2022) - Cannabinoid-Induced Seizures
- Phase-1 pilot, 2 & 3 mg inhaled
- Psychotomimetic 5.5 mg study
Rat tolerance & CB1 desensitisation- Rat Tolerance and CB1 Desensitization
- Schneir et al. (2011) - Synthetic Cannabinoid Intoxication
- Severe toxicity with seizures
Automated synthesisInformation aggregated and synthesized using an autonomous workflow built by Josie Kins.
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