Iron deficiency has been shown to effect the dopaminergic system. Iron deficient rats have low dopamine D2 receptor levels and modified dopamine-mediated behaviors, including reversal of circadian cycles of these behaviors. Abnormal iron deposits have been found in the brains of schizophrenics in CT and post mortum studies. We examined serum iron levels at 0800, 1700 and 2400 hours in 26 medication free schizophrenic patients in acute psychotic relapse and compared them to iron levels in a normal control group. The results show significant decreases in the iron levels at 1700 and 2400, and a non significant drop in the 0800 levels. A feedback mechanism involving iron and dopamine is proposed.