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> In recent years, online forum users have begun to discuss recreational use of these four synthetic opioids and commonly compared these four synthetic opioids to other traditionally abused opioids, such as morphine and fentanyl (schedule II substances). However, unlike these two drugs that have FDA-approval for use in specific medical treatments, the four synthetic opioids have no currently approved medical use and, based on positive identifications of these four substances in forensic drug exhibits and toxicology samples, are likely to be trafficked and abused similarly to other synthetic opioids, such as brorphine (schedule I).