title: Transmethylation hypothesis of schizophrenia: methionine and nicotinic acid.
abstract: The transmethylation hypothesis of schizophrenia was reviewed with considerations that large doses of methionine when combined with a monoamine oxidase inhibitor lead to exacerbation of psychotic symptoms in a significant percentage of chronic schizophrenic patients. It was noted that nicotinic acid in the dosage of 3,000 mg/day can neither prevent nor counteract the psychopathology thus induced.
mesh_terms: D002394:Catechol O-Methyltransferase / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D008715:Methionine / Q000008:administration & dosage / Q000009:adverse effects / Q000378:metabolism*; D008745:Methylation; D008780:Methyltransferases / Q000378:metabolism; D008996:Monoamine Oxidase Inhibitors / Q000008:administration & dosage; D009539:Nicotinic Acids / Q000008:administration & dosage*; D012559:Schizophrenia / Q000209:etiology / Q000378:metabolism*
chemical_list: D008996:Monoamine Oxidase Inhibitors; D009539:Nicotinic Acids; D008715:Methionine; D008780:Methyltransferases; D002394:Catechol O-Methyltransferase