In this regard, available evidence shows that while morphine and heroin are liable to attenuate the immune response, long-acting opioids that are used in withdrawal treatment, such as methadone and buprenorphine, are largely devoid of immunosuppressive activity. Opioids can also influence the immune function through the activation of the descending pathways of the hypothalamus-pituitary axis (HPA) and the sympathetic nervous system (Vallejo et al., 2004). This review on role of opioidergic system in humoral immune response summarizes the effect of opiate receptor polymorphism on innate and adaptive immunity, identifies the role of the mu opioid receptor in these functions,.
