Cannabinol (CNB) is a non-psychoactive cannabinoid found only in trace amounts in Cannabis, and is mostly found in aged Cannabis. Pharmacologically relevant quantities are formed as a metabolite of tetrahydrocannabinol (THC).CNB acts as a partial agonistat the CB1 receptors, but has a higher affinity to CB2 receptors; however, it has lower affinities relative to THC. Degraded or oxidized cannabis products, such as low-quality baled cannabis and traditionally produced hashish, are high in CNB, but modern production processes minimize the formation of CNB.
Unlike other cannabinoids, CNB does not stem from cannabigerol (CBG). There is no clinical evidence that THC breaks down naturally into CNB once the THC has become decarboxylated and forms delta-9 THC. CNB is formed by decarboxylation of cannabinolic acid.