5F-ADB (also known as 5F-MDMB-PINACA) is an indazole-based synthetic cannabinoid from the indazole-3-carboxamide family, which has been used as an active ingredient in synthetic cannabis products and has been sold online as a designer drug. 5F-ADB is a potent agonist of the CB1 receptor, though it is unclear whether it is selective for this target. 5F-ADB was first identified in November 2014 from post-mortem samples taken from an individual who had died after using a product containing this substance. Subsequent testing identified 5F-ADB to have been present in a total of ten people who had died from unexplained drug overdoses in Japan between September 2014 and December 2014. 5F-ADB is believed to be extremely potent based on the very low levels detected in tissue samples, and appears to