Addressing Hazards from Unscheduled Novel Psychoactive Substances as Research Chemicals: The Case of U-50488.

Increased experimentation with easily accessible synthetic opioids is posing a hazard to the public. We discuss one such synthetic opioid, U-50488. Much is unknown about U-50488; however, due to its structural similarity to U-47700, there is possible risk associated with its use. Curtailing the use of synthetic opioids such as U-50488 will require a concerted effort targeting multiple problems.