Is the antidepressant efficacy of ketamine and esketamine mediated via opioid mechanisms?
European Psychiatry 2026 Andy Lu, Heidi Xu, Gia Han Le et al. 4 citations
The reported mixed findings suggest that the opioid system may exert a partial mediating effect of ketamine in TRD. However, given the inconsistent attenuation of ketamine's antidepressant effects by opioid receptor antagonists, the opioid system likely functions as a context-dependent modulator rather than a primary mediator, particularly at standard antidepressant doses.