Cyclosporine alters opiate withdrawal in rodents

Opiates exert numerous effects on all levels of the central nervous system with tolerance, physical dependence and withdrawal being characteristics of this drug class. The degree of dependence is directly correlated to the intensity of withdrawal. Therefore, success in modifying the withdrawal syndrome may shed light on the dynamics of opiate addiction. The present study demonstrates that cyclosporine, a widely used immunosuppressive drug, considerably modified the behavioral signs of a naloxone-induced abstinence syndrome in morphine-addicted rats. In previous experiments, alpha-interferon has shown similar results. The similarity in actions of these two immunomodulator drugs is discussed and we suggest that opiate addiction may involve the immune system.