Scenario: 64 year old female developed C.Diff. Colitis in ICU. 2 days later urine color changed to dark brown and progressively became black! What is your diagnosis? - Choose one

A) Worsening C. Diff. Colitis despite treatment
B) Developing Rhabdomyolysis
C) Benign side effect of Metronidazole treatment - continue Metronidazole
D) Life threatening side effect of Metronidazole treatment - stop Metronidazole



Answer: C

Darken urine - dark brown to black - is a benign side effect of Metronidazole (Flagyl). It is due to water-soluble pigments formed during metabolism. No intervention is needed.