Cannabinol (CBN) is a weak psychoactive cannabinoid usually found in trace amounts (<1%) in Cannabis sativa and Cannabis indica. It is the final metabolite of cannabigerolic acid (CBGa) through the tetrahydrocannabinol (THC) biosynthetic pathway, and can be indicative of the age of the cannabis.
Because it is a somewhat selective CB2 receptor agonist, it is used experimentally as an immunosuppressant, which can be useful in autoimmune related diseases such as lupus and type 2 diabetes. CBN is the cannabinoid with very promising antibacterial properties that may prove useful in treating drug resistant bacterial infections . It has also been implicated as a bone stimulant, and may help regenerate bone mass lost due to osteoporosis . Finally, CBN is the primary appetite stimulant in cannabis, and may therefore be used to treat patient under-nutrition caused by nausea.