Skip to main content
Clinical significance of color of urine
- The color of normal urine ranges from pale to dark yellow and amber, depending on the concentration of the urochrome.
- The most frequent pathologic conditions that can cause color changes of the urine are gross hematuria, hemoglobinuria, or myoglobinuria (pink, red, brown, or black urine);
- bilirubinuria (darkyellow to brown urine); and
- massive uric acid crystalluria (pink urine).
- Less frequent causes are urinary infection, mainly from Klebsiella spp., Proteus mirabilis, Escherichia coli, Providencia stuartii, or Enterococcus spp. in patients with permanent bladder catheter (purple urine, sometimes called “purple urine bag syndrome”)
- chyluria (white milky urine); and
- porphyrinuria (associated with the excretion in the urine of porphobilinogen) and
- alkaptonuria (red urine turning black on standing).
- rifampin (yellow-orange to red urine);
- desferrioxamine (pinkish urine);
- phenytoin (red urine);
- chloroquine and nitrofurantoin (brown urine);
- triamterene, propofol, and blue dyes of enteral feeds (green urine)
- ; methylene blue (blue urine);
- metronidazole, methyldopa, and imipenem-cilastatin (darkening on standing).
- beetroot (red urine),
- senna and rhubarb (yellow to brown or red urine), and
- carotene (brown urine).