"Clinical and public health responses to date have focused on acute toxicity from NPS. This attention has grown in previous years with the increased reportings of overdose associated with NPS in several countries. Current examples include rising mortality from benzodiazepine NPS in Scotland (etizolam implicated in 57% of all drugrelated deaths in 2018);123 opioid NPS in North America (fentanyl analogues detected in 20·6% of opioid overdose deaths occurring between July, 2016, and June, 2017, in 10 US states);33 and from synthetic cannabinoids in New Zealand (reportedly in excess of 40 deaths linked to synthetic cannabinoids in 2017–18).124

"In almost all clinical situations of acute toxicity, there is a restricted capacity for rapid confirmation of NPS to inform management: many rapid testing measures are not sensitive to NPS and cannot keep pace with new substances. Current guidance from the Novel Psychoactive Treatment UK Network (NEPTUNE) recommend diagnosis on the basis of clinical assessment and recognition of the clinical toxidrome given that most NPS have similar effects to the more established illicit drugs they are intended to mimic (synthetic cannabinoids being a notable exception).13,14,125 The NEPTUNE guidelines recommend symptomatic and supportive management, particularly in the absence of research on the management of acute toxicity for the varied NPS.13,14,125 The exception is opioid NPS overdose, for which the relative higher potency of some opioid NPS might require changes in clinical management. For example, clinical guidance based on reports from fentanyl analogue overdoses suggest some cases might require higher doses of naloxone, rapid escalation of naloxone dosing, and a longer observation period in a hospital setting than other opioids.125"

Source

Amy Peacock, PhD, Raimondo Bruno, PhD, Natasa Gisev, PhD, Prof Louisa Degenhardt, PhD, Prof Wayne Hall, PhD, Roumen Sedefov, MD, et al. New psychoactive substances: challenges for drug surveillance, control, and public health responses. The Lancet. Volume 394, Issue 10209, p1668-1684, November 02, 2019. Published:October 23, 2019.