Elevated systemic CRP levels have been noted in numerous conditions associated with peripheral and central neural damage as well as impaired neuroprotection, i.e., Alzheimer’s disease (Song et al. 2015; Kempuraj et al. 2017; Gabin et al. 2018), Parkinson’s disease (Sawada et al. 2015; Umemura et al. 2015; Qiu et al. 2019), depression (Felger et al. 2018), opioid use disorder (Wang et al. 2018), or following chimeric antigen receptor T cell (CAR-T) therapy in cancer (Santomasso et al. 2018; Wang and Han 2018). This evidence concerns the gene CRP and opioid use disorder.