title: Letter: Tryptophan in depression.
mesh_terms: D002986:Clinical Trials as Topic; D003863:Depression / Q000188:drug therapy*; D004357:Drug Synergism; D006801:Humans; D007099:Imipramine / Q000627:therapeutic use; D008996:Monoamine Oxidase Inhibitors / Q000627:therapeutic use; D014364:Tryptophan / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D008996:Monoamine Oxidase Inhibitors; D014364:Tryptophan; D007099:Imipramine