Orexin A in men with heroin use disorder undergoing methadone maintenance treatment.

Orexins have played a role in reward-seeking and addiction-related behavior. There are few reports in the literature on serum levels of orexins in patients with heroin use disorder (HUD) undergoing methadone maintenance treatment (MMT). The aim of this study was to investigate the serum levels of orexin A in HUD patients undergoing MMT. Fifty male HUD patients undergoing MMT and 25 healthy males were enrolled for this study. Serum orexin A were measured with assay kits. Using analysis of covariance (ANCOVA) with body mass index (BMI) adjustments, the serum levels of orexin A in HUD men undergoing MMT were found to be significantly higher than in healthy controls. In conclusion, our results suggest that MMT might increase orexin A levels in HUD patients.