Could a common food preservative help treat Hard-to-Treat schizophrenia?

This study tests whether adding sodium benzoate—a substance that affects brain glutamate—to standard antipsychotic medication can improve symptoms and thinking in people with treatment-resistant schizophrenia. About 90 adults who have not responded well to at least two antipsychotics will receive either sodium benzoate or a placebo for 8 weeks. Researchers will use brain scans, blood tests, and symptom ratings to see if the treatment works and to identify who might benefit most.