Definition

The usual color of urine is straw-yellow. Abnormally-colored urine may be cloudy, dark, or blood-colored.

Alternative Names

Discoloration of urine

Causes

Abnormal urine color may be caused by infection, disease, medicines, or food you eat.

Cloudy or milky urine is a sign of a urinary tract infection, which may also cause a bad smell. Milky urine may also be caused by bacteria, crystals, fat, white or red blood cells, or mucus in the urine.

Dark brown but clear urine is a sign of a liver disorder such as acute viral hepatitis or cirrhosis, which causes excess bilirubin in the urine. It can also indicate severe dehydration or a condition involving the breakdown of muscle tissue known as rhabdomyolysis.

Pink, red, or lighter brown urine can be caused by:

• Beets, blackberries, or certain food colorings
• Hemolytic anemia
• Injury to the kidneys or urinary tract
• Medicines
• Porphyria
• Urinary tract disorders that cause bleeding
• Blood from vaginal bleeding
• Tumor in the bladder or kidneys

Dark yellow or orange urine can be caused by:

• B complex vitamins or carotene
• Medicines such as phenazopyridine (used to treat urinary tract infections), rifampin, and warfarin
• Recent laxative use

Green or blue urine is due to:

• Artificial colors in foods or medicines
• Bilirubin
• Medicines, including methylene blue
• Urinary tract infections

When to Contact a Medical Professional

See your health care provider if you have:

• Abnormal urine color that cannot be explained and does not go away
• Blood in your urine, even once
• Clear, dark-brown urine
• Pink, red, or smoky-brown urine that is not due to a food or medicine

What to Expect at Your Office Visit

Your provider will perform a physical exam. This may include a rectal or pelvic exam. Your provider will ask you questions about your symptoms such as:

• When did you first notice a change in urine color and how long have you had the problem?
• What color is your urine and does the color change during the day? Do you see blood in your urine?
• Are there things that make the problem worse?
• What types of foods have you been eating and what medicines do you take?
• Have you had urinary or kidney problems in the past?
• Are you having any other symptoms (such as pain, fever, or increase in thirst)?
• Is there a family history of kidney or bladder cancers?
• Do you smoke or are you exposed to significant second hand tobacco?
• Do you work with certain chemicals such as dyes?

Tests that may be done include:

• Blood tests, including liver function tests
• Ultrasound of kidneys and bladder or CT scan
• Urinalysis
• Urine culture for infection
• Cystoscopy
• Urine cytology

References

Elsamra SE. Evaluation of the urologic patient: history and physical examination. In: Partin AW, Domochowski RR, Kavoussi LR, Peters CA, eds. Campbell-Walsh-Wein Urology. 12th ed. Philadelphia, PA: Elsevier; 2021:chap 1.

Gharavi AG, Landry DW. Approach to the patient with renal disease. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 100.