Experimental Study on the Postmortem Redistribution of the Substituted Phenethylamine, 25B‐NBOMe

2‐(4‐Bromo‐2,5‐dimethoxyphenyl)‐N‐(2‐methoxybenzyl)ethanamine (25B‐NBOMe) is a substituted phenethylamine, which has become highly prevalent worldwide since 2014. Recently, in an autopsy case involving fatal 25B‐NBOMe intoxication, we found the postmortem increase of 25B‐NBOMe concentration in the cardiac blood approximately 2 days after death. The aim of this study was to investigate the distribution of 25B‐NBOMe and reproduce the postmortem redistribution using a rat model. Sprague‐Dawley rats were killed 30 min after intraperitoneal injection of 25B‐NBOMe (0.5 mg/kg) and left for 0, 3, 6, 9, 15, or 24 h (six rats at each time point). Postmortem 25B‐NBOMe concentrations in the cardiac blood increased by more than 10‐fold at 6‐h postmortem. 25B‐NBOMe accumulated primarily in the lung. Moreover, this postmortem redistribution occurred even in rats that had died 1 week following the 25B‐NBOMe administration. These findings indicate that attention should be paid to sample collection and data interpretation in the toxicological analysis of 25B‐NBOMe.