Under normal conditions, the urine is either colorless or may display various shades of yellow. A brown colored urine is not a normal occurrence. The urine may display various shades of brown color under a variety of abnormal conditions. In some cases, the shade of brown may be dark enough to border on black.
Depending on the shade of brown color, people may describe the urine as tea, coffee or cola-colored urine. In addition to changes in the color, the urine may also undergo a change in consistency. For example, brown colored urine may also have a murky appearance rather than a clear consistency.
Why is urine brown?
Brown colored urine can occur due to the presence of certain metabolites, supplements, and drugs in the urine. Consumption of certain foods and beverages can also impart a brownish color to the urine. Among pathological causes, the presence of blood in the urine (technically referred to as hematuria) is a common cause of brown colored urine.
Since blood is red in color, one might expect the urine to turn red when mixed with blood. However, breakdown of hemoglobin and other red blood cell components commonly imparts a brown color to the urine. Presence of myoglobin protein can also make the urine appear brown in color. In case of hematuria, the urine may appear to contain brownish-black specks that are similar to coffee grounds.
Read more on blood clots in urine.
Less common causes of brown colored urine include the presence of melanin pigment and fecal particles in the urine. Melanin pigment may get mixed with the urine in conditions such as melanoma. Fecal particles in urine (fecaluria) may appear as brownish specks. Fecaluria results from the formation of a fistula between the colon/rectum and the urinary bladder.
Signs and symptoms
Light or dark brown colored urine is usually a symptom of an underlying disease. Many different disease conditions can cause the urine to turn brown. Depending on the specific cause, brown colored urine may also be accompanied by other signs and symptoms. Most of the accompanying signs and symptoms do not arise from the lower urinary tract (urinary bladder and urethra).
The following are some of the signs and symptoms that may be present along with brown colored urine:
- Pain in the abdominal flanks
- Pain in the abdomen
- Changes in appetite
- Changes in the color of the eyes and skin
- Unintentional weight loss
Causes of brown urine
Any change in the color of urine can be caused by both pathological and non-pathological causes. Brown colored urine is no exception. Both pathological and non-pathological causes are known to impart various shades of brown color to the urine. The following are some of the potential non-pathological causes of brown colored urine:
Consumption of certain foods and beverages can result in a brownish urine color. Examples of dietary components that can cause brownish urine include aloe, rhubarb, blackberries, and beets.
Brown colored urine may also result from intake of certain medications such as chloroquine, levodopa, furazolidone, nitrofurantoin, primaquine, methocarbamol, and metronidazole.
Excessive use of herbal supplements such as senna and cascara can also cause excretion of brown colored urine.
Strenuous exercise can result in hematuria that is characterized by brown urine. March hematuria is an example of such a condition.
In some cases, the urine may appear brown due to its reaction with the detergents and chemicals present in the toilet water.
Read more on feces in urine.
Diseases that may cause brown urine
The following are some of the possible pathological causes of brown colored urine:
- Infections: Examples of infectious causes of brown urine include yellow fever, blackwater fever, and leptospirosis. Blackwater fever is a complication of malaria. In this context, it is important to consider if the person with brown colored urine has recently travelled to Africa and other places where these infections are predominant.
- Liver diseases: Cirrhosis and viral hepatitis are examples of liver diseases that can cause brown colored urine.
- Kidney diseases: Glomerulonephritis and trauma to the kidneys can also result in brown colored urine.
- Iron toxicity: Brown colored urine may result from accumulation of abnormally high levels of iron in the body.
- Hematuria: As mentioned previously, the presence of blood in the urine can impart a brown color to the urine due to breakdown of hemoglobin. Hematuria can occur without any accompanying pain.
- Melanoma: Melanoma refers to a very serious type of malignant skin cancer. Excess melanoma pigment in melanoma can impart the urine a brownish color.
- Porphyria: Porphyria refers to a group of hereditary metabolic diseases that are characterized by impaired metabolism of hemoglobin. Excretion of hemoglobin in the urine can make the urine brown.
- Tyrosinosis: Tyrosinosis refers to a metabolic disease that is characterized by faulty metabolism and excretion of tyrosine in the urine.
Diagnosis (Tests and Scans)
Diagnosis of the underlying cause of brown colored urine may require various diagnostic tests. A doctor may be able to isolate potential causes based on the assessment of symptoms, medical history, and clinical examination of the patient. After isolating the most likely causes, the doctor may perform differential diagnosis based on specific tests. Examples of some of the tests that may be conducted include urine dipstick, urea and electrolyte tests, urinalysis, and blood tests (such as complete blood count).
Treatment for brown urine
Since brown colored urine is a symptom, it cannot be corrected without treating the underlying condition. An appropriate treatment can be prescribed only after an accurate diagnosis of the underlying cause of brown urine. Some simple measures that may help in many of the conditions that cause brown colored urine are listed below:
- Drinking lots of fluids.
- Strict bed rest.
- Eating healthy foods that are devoid of spices and preservatives.
- Avoiding sexual intercourse.
- Discontinuing intake of herbal and nutritional supplements.
- Avoiding self-medication.
It is important to note that chronic medications prescribed by a doctor should not be discontinued abruptly without consulting the doctor. Since brown colored urine usually indicates an underlying pathology, it is important to seek immediate medical attention rather than adopting a wait-and-watch policy. Some of the potential causes of brown colored urine can be lethal, if not treated.