Reduced haloperidol is an active metabolite of haloperidol . It is formed via reduction of haloperidol by ketone reductase. Reduced haloperidol inhibits radioligand binding to sigma-1 and dopamine D2 receptors (Kis = 1.4 and 31 nM, respectively) and stimulates brain-derived neurotrophic factor (BDNF) secretion from CCF-SSTG1 and U87MG astrocytic glial cells. It also inhibits norepinephrine, dopamine, and serotonin (5-HT) reuptake (Kis = 21, 25, and 33 μM, respectively, in COS-7 cells expressing the human transporters). Reduced haloperidol (0.5 mg/kg) increases latency to paw withdrawal in mouse models of capsaicin- but not force-induced mechanical hypersensitivity.