Dark Urine: Main Causes & Warning Signs

Dark urine is often a sign of dehydration, when the body does not get enough fluids and urine becomes more concentrated. It may also be linked to conditions like urinary tract infections, kidney stones, or liver problems.

Other symptoms can appear along with dark urine, such as pain or burning when urinating, lower back pain, fever, or pale stools. These signs may indicate a more serious condition that requires medical evaluation and treatment.

The causes of dark urine range from simple habits, like holding urine or not drinking enough water, to kidney or liver disease. Treatment depends on the cause and may include increasing fluid intake, medications, or medical procedures when needed.

Why is my urine dark?

The main causes of dark urine are: 

1. Inadequate water intake

The most common cause of dark urine is not drinking enough water during the day. When fluid intake is low, urine becomes more concentrated, resulting in a darker color and stronger odor.

What to do: Drink plenty of fluids throughout the day. Water, teas, and natural juices are good options, as well as foods with high water content.

Producing a large amount of light-colored urine is a sign that your body is well hydrated, which helps maintain normal body functions.

2. Holding your urine

Holding your urine for long periods can cause it to appear darker. When urine stays in the bladder for too long, the substances that are normally eliminated begin to accumulate, which can change its color.

In addition, regularly holding your urine can increase the risk of complications such as urinary tract infections (UTIs), incontinence, and kidney stones.

What to do: To avoid these problems, try to use the toilet whenever you feel the need to urinate, even if your bladder is not completely full. Urinating regularly helps remove waste substances from the urinary tract and reduces the risk of developing bladder problems over time.

3. Urinary tract infections

A urinary tract infection (UTI) is another common cause of dark urine, particularly in people who experience recurrent infections. UTIs can affect kidney function, leading to more concentrated urine that may contain small amounts of blood.

According to the CDC, pain or burning during urination (dysuria) is a common symptom of a urinary tract infection. Other UTI symptoms may include fever and a feeling of pressure or heaviness in the lower abdomen.

What to do: It is important to see a healthcare provider for testing if you are experiencing symptoms of a UTI. The infection is typically treated with antibiotics. Drinking plenty of fluids and maintaining a healthy diet can also help speed up recovery.

4. Kidney stones

Kidney stones can cause urine to appear darker, often because the condition is linked to reduced fluid intake. They may also cause small amounts of blood to appear in the urine, which further darkens its color.

In addition to dark urine, kidney stones can cause severe back pain and pain during urination.

What to do: Imaging tests are usually needed to identify the location and size of the kidney stone. Once the stone is confirmed, a healthcare provider can decide on the most appropriate treatment. This may include anti-inflammatory medications to relieve discomfort and medicines that help dissolve the stone so it can pass through the urine.

In more severe cases, when there are multiple stones or one large stone, a minor procedure may be required to remove it.

5. Liver problems

Certain liver conditions, such as cirrhosis and hepatitis, can impair liver function and lead to darkened urine. This happens when inflammation and reduced liver activity prevent bilirubin from being properly processed.

Bilirubin is a pigment formed from the breakdown of hemoglobin, and when it accumulates in the body, higher amounts are excreted in the urine. 

It is also common to notice stools that look white or pale. According to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), this can happen when bilirubin, a substance that normally gives stool its brown color, does not reach the intestines as it should.

What to do: If you notice any signs or symptoms of liver problems, you should see a healthcare provider for evaluation. Tests may be ordered to identify the cause of the dark urine and guide treatment, which may include medications or dietary changes.

6. Kidney disease

Certain health conditions can affect how well the kidneys function and interfere with their ability to filter and reabsorb substances from the blood. As a result, the urine may become more concentrated and appear darker.

The kidneys can become overloaded due to factors such as diets high in protein and calcium, excessive supplement use, chronic UTIs, kidney stones, or high blood pressure.

What to do: It is important to consult a healthcare provider who can determine the underlying cause of the kidney problem to help prevent further or permanent damage that could lead to kidney failure.

Depending on the cause of the dark urine, the provider may prescribe anti-inflammatory medications, antibiotics, or diuretics. In some cases, surgery or dietary adjustments may also be recommended.

7. Nephritic syndrome

Nephritic syndrome is a kidney disorder that can cause blood to appear in the urine, giving it a dark color. It is also linked to high blood pressure, reduced urine output, and swelling.

If not diagnosed and treated promptly, it can lead to acute kidney injury, resulting in elevated levels of urea and creatinine in the blood.

What to do: If you have signs or symptoms of nephritic syndrome, it is important to see a urologist for proper evaluation and testing.

After confirming the diagnosis, the doctor may prescribe antihypertensive medications to manage blood pressure, diuretics to reduce swelling, and corticosteroids to decrease inflammation. In some cases, antibiotics may also be recommended.

8. Blood in the urine

The presence of blood in the urine can also cause the urine to appear darker. This may result from several conditions, such as a UTI affecting the bladder or kidneys, the use of medications like warfarin or aspirin, or cancers of the kidneys, bladder, or prostate.

Some women may notice what looks like blood in their urine during the first days of their period. This usually happens when menstrual blood mixes with urine in the toilet, making the urine look darker or slightly red.

What to do: Blood in the urine should always be checked by a healthcare provider. The provider will likely do a physical exam and order some tests to find the cause and start treatment if needed.

During your period, pay attention to symptoms such as fever or a burning sensation when you urinate, as these could be signs of a UTI.