Cannabinol (CBN) is a weak psychoactive cannabinoid found only in trace amounts in Cannabis sativa and Cannabis indica. It is mostly a metabolite of tetrahydrocannabinol (THC). CBN acts as a weak agonist of CB1 receptors but has a higher affinity to CB2 receptors, with lower affinities in comparison to THC. Because of its somewhat selective CB2 agonism, it is used experimentally as an immunosuppressant.
- Cannabinol at Wikipedia