Article: Anxiety In Your Head Could Come From Your Gut The enzyme HPHPA from Clostridia species bacteria in the gut can affect brain chemistry, leading the anxiety and psychosis symptoms. HPHPA — full name 3-(3-hydroxyphenyl)-3-hydroxypropionic acid — can cause an excess production of dopamine and reduced levels of norepinephrine, leading to mental symptoms. HPHPA causes deactivation of an enzyme so that dopamine cannot be converted to the neurotransmitter neuroepinephrine, and that causes a build-up of dopamine. HPHPA has been found in higher concentrations in urine samples of children with autism.ᐞ This article says that treatment with metronidazole, vancomycin, or high doses of probiotics of individuals with high urinary values of HPHPA has led to significant clinical improvements or remissions of psychosis. HPHPA is produced by the Clostridia species: Clostridium sporogenes Clostridium botulinum Clostridium caloritolerans Clostridium mangenoti Clostridium ghoni Clostridium bifermentans Clostridium difficile Clostridium sordelli Also of interest: Inhibition of dopamine conversion to norepinephrine by Clostridia metabolites appears to be a (the) major cause of autism, schizophrenia, and other neuropsychiatric disorders. All these factors can now be monitored in The Great Plains Laboratory Organic Acids Test. William Shaw, Ph.D., The Great Plains Laboratory.