In those rats qualified to self-administer oxycodone, administration of an immunoconjugate vaccine (Oxy-TT) reduced oxycodone concentrations in brain by 50% and vaccination lowered the rat's oxycodone intake and delivered protection versus the reinforcing effects of oxycodone. The exact neuronal pathways that cause opioid addiction and abuse want further more investigating. https://wockusa.com/product/fentanyl-powder/