JWH-018JWH-018 (1-pentyl-3-(1-naphthoyl)indole)

naphthalen-1-yl(1-pentyl-1H-indol-3-yl)methanone

Aliases.AM-678 · Spice constituent · K2 constituent

The first SCRA detected on the illicit market (« Spice » 2008). The reference compound of the first wave.

Updated on 1 May 2026

Level of detail

Harm-reduction warning

No characterised human dose: animal / in vitro data only. Effect profile, safety margin and acute toxicity are not documented in human clinical practice. Extremely potent compound: severe effects, seizures and deaths reported in the literature.

Identifiers

Formula: C₂₄H₂₃NO
Molar mass: 341.45 g·mol⁻¹
CAS: 209414-07-3
PubChem CID: 10382701
First described: 1995
Origin: Academic research (J.W. Huffman, Clemson)
InChIKey: JDNLPKCAXICMBW-UHFFFAOYSA-N

In plain terms

JWH-018 is the ancestor of street synthetic cannabinoids (« Spice », « K2 »). Far more potent and more dangerous than THC: overdoses, anxiety attacks, vomiting, convulsive seizures.

Receptors and activity

CB1
Ki ≈ 9,0 nMAgonist
CB2
Ki ≈ 2,9 nMAgonist

Agonist
Partial agonist
Antagonist
Modulator
Inverse agonist

Hover over a row for the precise value (Ki, EC50…)

Subjective signature

Hover over an axis to read its definition.

Calm
35
Clarity
25
Sleep
50
Appetite
60
High
90

Editorial estimate, not clinical.

Pharmacology

JWH-018 is the prototypical naphthoylindole synthesised by the academic chemist John W. Huffman (Clemson University, SAR series, 1990s). Pharmacological characterisation by Aung et al. 2000 (PMID 10785570): CB1 Ki = 9.0 nM, CB2 Ki = 2.9 nM. A full agonist (and not a partial one like THC) - which partly explains the more severe clinical profile: convulsions, hyperaemia, acute vomiting, agitation. The first SCRA identified on the illicit market (« Spice » mixture seized in Frankfurt, October 2008). In France: listed by name in Annex IV by the **Decree of 24 February 2009** (NOR SASP0900303A) - the first French intervention on SCRAs.

Key sources.

Aung · Drug Alcohol Depend 2000PMID 10785570

Origin (pharmaceutical research → illicit market)

A naphthoylindole synthesised in order to study the CB1 pharmacophore; diverted to the illicit « Spice / K2 » market from 2008 onwards (first detected in Frankfurt)