Medetomidine in the Unregulated Drug Supply in the US

"Medetomidine was identified in primary abundance in seven US states during the analysis period (New York, Pennsylvania, North Carolina, Michigan, Ohio, Florida, Virginia) (Appendix B). Medetomidine-containing samples were most often white and in powder form (Table 1). Commonly endorsed sensations included ‘sedating’ (32.4%), ‘stronger’ (25.0%), ‘unpleasant’ (16.9%), ‘weird’ (13.2%) and ‘more down’ (11.0%). Sample donors most often expected samples to contain fentanyl (86.9%), xylazine (42.3%) and/or heroin (23.1%).

"Most medetomidine-positive samples also contained fentanyl (58.8%) and/or xylazine (55.9%) (Table 2). Including trace substances, GCMS identified a median of eight substances in medetomidine-containing samples (range: 2–17) compared with a median of three substances in all other samples (range: 1–19) (Table 3).

"Hallucinations were reported in 17.6% of samples containing medetomidine overall (n = 24) and 25.0% of such samples with recorded sensation data, as compared with 1.2% and 2.3% in the overall dataset. Adjusting for covariates, samples containing medetomidine were significantly more likely to be associated with hallucinations compared with other samples, with an aPR of 11.95 (95% confidence interval [CI] 6.36, 22.44) (Table 4). Among covariates, selected nonpsychoactive fillers (aPR 0.41, 95% CI 0.24, 0.70) and fentanyl precursors and impurities (aPR 0.46, 95% CI 0.22, 0.96) were associated with lower prevalence of hallucinations. Hallucinations were significantly more common overall in the Northeast, South and Midwest compared with the West during the study period. Model results were robust to sensitivity analysis, though attenuated (aPR 9.11, 95% CI 4.81, 17.23) (Appendix C). In free response, participants described medetomidine-related hallucinations as ‘intense’, ‘trippie [sic] like DMT’, ‘psychedelic’ and ‘dissociative seeming’ (Appendix D)."