Urine consists of excess water and waste products that the kidneys filter from the blood. It can range from pale yellow to dark amber depending on the ratio of water to waste products.
Many things can affect the color of urine. Most of these are harmless, but a change in color can sometimes signal a health problem.
This article will look at five common causes of dark urine and treatment options.
Dark urine is usually a sign of dehydration. Dehydration occurs when there is not enough water in the body.
It can lead to dark urine as well as:
Children, older adults, and people living with severe illnesses, such as cancer, are more prone to dehydration.
In most cases, people can treat dehydration by drinking more clear fluids, such as water and herbal tea.
People should seek medical advice if they have any, some, or all of the following symptoms:
- very dry mouth and tongue
- skin that moves back very slowly after being pinched
- weak or absent pulse
- very low blood pressure
- minimal or no urine
Some foods and drinks can cause a change in the color or smell of urine.
Beets and blackberries can turn the urine red and eating rhubarb can result in a dark brown or tea-like color.
Some medications can also cause changes in urine color:
- Senna, chlorpromazine, and thioridazine can result in red urine.
- Rifampin, warfarin, and phenazopyridine can result in orange urine.
- Amitriptyline, indomethacin, cimetidine, and promethazine can result in blue or green urine.
- Chloroquine, primaquine, metronidazole, and nitrofurantoin can result in dark brown or tea-colored urine.
Red blood cells develop in the bone marrow. The body usually destroys old or faulty red blood cells in the spleen in a process called hemolysis.
When the body mistakenly destroys too many red blood cells, a person might develop hemolytic anemia.
Genetic blood disorders, such as sickle cell disease or thalassemia, can also lead to hemolytic anemia. It is also a potential side effect of some medicines and can sometimes occur after blood transfusions.
In addition to dark urine, symptoms of hemolytic anemia include:
- heart palpitations
- pale skin
- a headache
- jaundice, or yellowing skin and eyes
- an enlarged spleen or liver
In severe cases, hemolytic anemia can lead to:
- back and abdominal pain
Urinary tract infections (UTIs) happen when bacteria get into the bladder, usually through the urethra. Women tend to develop UTIs more often than men, and many people know them as bladder infections or cystitis.
Symptoms of a UTI include:
- pain or burning while urinating
- pain or pressure in the abdomen
- frequent urges to urinate
- urine that is cloudy, dark, or appears bloody
The hepatitis C virus (HCV) can cause an infection of the liver. It has few symptoms during the early stages, so many people do not know they have it until liver damage starts causing problems. Because it affects how the liver processes waste, HCV may cause dark urine.
People who received a blood transfusion or organ transplant before July 1992 or a blood product for clotting problems manufactured before 1987 are at risk of having HCV.
Other risk factors include sharing needles, having sex without a condom with a person who has HCV, and receiving tattoos using unsterile equipment.
If symptoms do occur, they usually appear within 2 weeks to 6 months of exposure to the virus. They are generally mild and may include:
- sore muscles
- joint pain
- nausea or poor appetite
- stomach pain
- itchy skin
- dark urine
People experiencing severe dehydration may need rehydration therapy. This process usually involves administering oral rehydration salts or fluids and electrolytes in the hospital.
Dark urine due to food, drink, or medications is not usually a cause for concern. The urine will return to its normal color once a person stops consuming whatever is causing the change.
Many mild cases of hemolytic anemia do not require treatment. For others, lifestyle changes can help control symptoms.
In severe cases of hemolytic anemia, blood transfusions, blood and bone marrow transplants, or surgery to remove the spleen may be necessary.
Doctors will usually prescribe a short course of antibiotics to treat UTIs. People with a severe infection may require a longer course of antibiotics. Some people may take pain relievers.
For many years, HCV treatments carried various potential side effects. However, new therapies can help treat many forms of the virus without severe side effects.
People showing signs of severe dehydration should seek medical attention straight away, as the condition can cause severe complications.
Anyone who thinks they may have a UTI should see a doctor for testing and possible antibiotic treatment. Without treatment, the infection may spread to the kidneys.
Anyone who suspects exposure to HCV should speak to a healthcare professional about getting tested. The virus can lead to severe liver damage if left untreated.