Recreational & Novel Psychoactive Substances

Overview & definition

Recreational and novel psychoactive substances (NPS) — the "legal highs", "designer drugs", "research chemicals" — are evolving, unpredictable, often-adulterated drugs that outrun the laboratory. The history is always unreliable: the user does not know the contents, and street names are marketing, not chemistry. Slight alterations of the basic chemical structure create an entirely new drug no longer covered by current laws, and the purity, exact pharmacokinetics and toxicity profile of each substance are largely unknown. Management is symptom-based, goal-directed supportive care, with benzodiazepines as a useful adjunct.^[2]

Two principles hold the whole topic together. First, treat the toxidrome, not the assumed agent — contents are unknowable in real time, adulterants are the rule, and the chemistry evolves faster than any assay. Second, reach for the benzodiazepine first for agitation and sympathomimetic or serotonergic toxicity; most of these substances have no specific antidote.^[2][1]

NPS fall into broad pharmacological families, grouped by drug class — synthetic cannabinoids, synthetic cathinones and other phenethylamines, novel benzodiazepines, novel synthetic opioids, dissociatives and potent hallucinogens such as the NBOMe series:^{[2][23][21][26][24]}

• Sedatives — GHB and its precursors GBL and 1,4-butanediol; designer benzodiazepines.^[1][23]
• Stimulants — MDMA/ecstasy and other phenethylamines; synthetic cathinones ("bath salts").^[4][17]
• Cannabinoids — synthetic cannabinoids (Spice, K2): direct CB1-receptor agonists, unlike the partial agonist THC.^[18]
• Dissociatives — ketamine and related arylcyclohexylamines.^[26]
• Opioids — non-fentanyl new synthetic opioids (the nitazenes) alongside fentanyl analogues.^[21]
• Psychedelics — the NBOMe series and other substituted phenethylamines.^[24]

References30ShowHide

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