It has been reported that schizophrenics exhibit a general “aromaturia.”1-4 The psychotomimetic effects of numerous aromatic organic compounds suggest that schizophrenia may be caused by endogenous production of a psychotogenic metabolite of a naturally occurring aromatic compound, such as phenylalanine, tyrosine, or tryptophan. Confirmation of the finding that the urine of schizophrenic patients contains unusual levels or types of aromatic compounds would favor the hypothesis that schizophrenia is caused by derangement of the metabolism of aromatic compounds, which, in turn, leads to the endogenous production of a psychotogenic agent.
The recognition and control of numerous irrelevant variables represent a recurrent difficulty in the study of schizophrenia. As part of a broad research program on the biological aspects of schizophrenia being carried out in this laboratory,5 both normal volunteers and a carefully selected10 group of schizophrenic patients have been maintained in similar environments
JAY D. M, ELWOOD H. L. Urinary Excretion of Phenolic Acids by Normal and Schizophrenic Male Patients. AMA Arch Gen Psychiatry. 1959;1(5):547-551. doi:10.1001/archpsyc.1959.03590050115014