title: Letter: Expectorant effect of glyceryl guiacolate.
mesh_terms: D001991:Bronchitis / Q000188:drug therapy*; D006140:Guaifenesin / Q000494:pharmacology / Q000627:therapeutic use*; D006801:Humans; D013183:Sputum / Q000187:drug effects
chemical_list: D006140:Guaifenesin