
Alternative name: Discolouration of urine
Definition: The usual colour of urine is straw-yellow. Abnormally coloured urine may be cloudy, dark or blood-coloured.
Causes
Abnormal urine colour 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.
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
- Medicine
- Porphyria
- Urinary tract disorders that cause bleeding
- Blood from vaginal bleeding
- Tumour 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 colours in foods or drugs
- Bilirubin
- Medicines, including methylene blue
- Urinary tract infections
When to Contact a Medical Professional
See your health care provider if you have:
- Abnormal urine colour 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 drug
What to Expect at Your Office Visit
The provider will perform a physical exam. This may include a rectal or pelvic exam. The provider will ask you questions about your symptoms such as:
- When did you first notice a change in urine colour and how long have you had the problem?
- What colour is your urine and does the color change during the day? Do you see blood in the 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)?
Tests that may be done include:
- Blood tests, including liver function tests
- Ultrasound of kidneys and bladder
- Urinalysis
- Urine culture for infection
- Cystoscopy
Related Tags
References
Gerber GS, Brendler CB. Evaluation of the urologic patient: history, physical examination, and urinalysis. In: Wein AJ, Kavoussi LR, Partin AW, Peters CA, eds. Campbell-Walsh Urology. 11th ed. Philadelphia, PA: Elsevier; 2016:chap 1.
Landry DW, Bazari H. Approach to the patient with renal disease. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 114.