Key points are not available for this paper at this time.
To the Editor.— We had the opportunity to observe a patient with amebic dysentery who, while undergoing treatment with metronidazole (Flagyl), 750 mg by mouth three times a day, passed dark-brown urine. Dark urine persisted during the fiveday course of therapy and it promptly subsided on termination of the drug. The urine specimen gave a negative reaction when tested for bile and blood. The Physicians Desk Reference does not mention that instances of darkened urine have been reported with this drug. Although the pigment which is probably responsible for this phenomenon has not been positively identified, it is almost certainly a metabolite of metronidazole.1It seems certain that it is of no clinical significance. Metronidazole ingestion should be added to the list of causes responsible for the production of dark urine.
Thomas A. Bruce (Mon,) studied this question.