title: Clinical trial of a new analgesic.
mesh_terms: D000700:Analgesics; D000983:Antipyrine / Q000627:therapeutic use; D002110:Caffeine / Q000627:therapeutic use; D002986:Clinical Trials as Topic; D006801:Humans; D010615:Phenacetin / Q000627:therapeutic use; D010619:Phenazines / Q000627:therapeutic use; D010919:Placebos
chemical_list: D000700:Analgesics; D010619:Phenazines; D010919:Placebos; D002110:Caffeine; D010615:Phenacetin; D000983:Antipyrine