title: Letter: Tryptophan plus a pyrrolase inhibitor for depression?
mesh_terms: D000328:Adult; D000493:Allopurinol / Q000008:administration & dosage / Q000627:therapeutic use*; D000818:Animals; D003863:Depression / Q000188:drug therapy*; D004341:Drug Evaluation; D004357:Drug Synergism; D004359:Drug Therapy, Combination; D006801:Humans; D066298:In Vitro Techniques; D009536:Niacinamide / Q000008:administration & dosage / Q000627:therapeutic use*; D051381:Rats; D014364:Tryptophan / Q000627:therapeutic use*; D014366:Tryptophan Oxygenase / Q000037:antagonists & inhibitors
chemical_list: D009536:Niacinamide; D000493:Allopurinol; D014364:Tryptophan; D014366:Tryptophan Oxygenase