JWH 398 N-(5-hydroxypentyl) metabolite-d5 is intended for use as an internal standard for the quantification of JWH 398 N-(5-hydroxypentyl) metabolite by GC- or LC-MS. JWH 398 is a synthetic cannabinoid (CB) that activates both CB1 and CB2 receptors (Ki = 2.3 and 2.8 nM, respectively).1 It has been reported to be an adulterant of herbal products.2,3 JWH 398 N-(5-hydroxypentyl) metabolite is a potential metabolite of JWH 398. Metabolism of structurally similar compounds leads to monohydroxylation of the N-alkyl chain, detectable in urine.4 This product is intended for forensic and research applications.WARNING This product is not for human or veterinary use.