Endogenous Metabolic Factor in Schizophrenic Behavior

Abstract
Exacerbations of schizophrenic behavior are associated with elevations of urinary tryptophan metabolites. Free tryptophan and methionine possibly arising from the breakdown of muscle protein may act like an endogenous metabolic factor which enhances behavioral worsening. Some of the apparently spontaneous activations of psychotic symptoms may be intensified by the endogenous liberation of these two compounds.