We know that the phytocannabinoids like THC and CBD, plus other cannabinoids frequently discovered, have therapeutic effects. We also know that our endocannabinoid system has receptors throughout the body that interact with the phytocannabinoids. This rather complex phenomenon involves endogenous and exogenous ligands and cross-reactions. When it comes to arthritis-related pain, the endocannabinoid system together with the cannabinoids derived from cannabis plays a major role in pain reduction. The human synovial fluid from arthritis joints contains anandamide and 2-arachidonyl glycerol, meaning that these endocannabinoids are synthesized when tissue is damaged.