Dopamine agonist-responsive depression.

Dopaminergic dysfunction is implicated in the pathophysiology of treatment-resistant depression. In this review, we describe the putative role of dopamine in depression, summarize the evidence for the efficacy of dopamine receptor agonists in the treatment of treatment-resistant depression, and discuss the underlying mechanisms by which these medications work. Both preclinical and clinical data suggest that adjunctive dopamine agonists could be a promising option for the treatment of such a condition, indicating that there is a dopamine agonist-responsive subgroup of depression. Future clinical studies are warranted to clarify unresolved issues regarding dopamine agonists such as long-term efficacy, efficacy as a monotherapy, and efficacy for juvenile and senile depression. Further basic research is also necessary to fully understand how dopamine acts in the brain of depressed patients.