Dechent et al (1999) studied the effect of oral creatine supplementation for 4 wk demonstrating a statistically significant increase of mean concentration of total creatine across brain regions. These findings suggest the possibility of using oral creatine supplementation to modify brain high-energy phosphate metabolism in subjects with various brain disorders, including schizophrenia and major depression. Recently, Rae et al (2003) reported that creatine supplementation for 6 weeks had a significant positive effect on both working memory and Raven matrices. Several independent lines of evidence suggest the possible involvement of altered cerebral energy metabolism in schizophrenia.