What should you know about dark brown black urine?

Highly concentrated urine can look dark after fluid loss, sweating, fever, vomiting, or heat exposure. Heat exhaustion may cause dehydration along with weakness, headache, nausea, and heavy sweating. Brown urine can also occur when bile pigments enter urine during liver inflammation such as hepatitis A or hepatitis B. Blood, muscle pigment, medicines, and some foods can change urine colour too; appearance alone cannot distinguish these causes.

If you have been losing fluid and can drink safely, take regular small amounts of water and move to a cool place. Observe whether the urine becomes lighter and record associated symptoms, recent exertion, heat exposure, foods, and medicines. Do not rely on hydration alone when the colour persists, returns, or comes with pain, fever, yellow skin, or reduced urination. Arrange clinical assessment for unexplained dark urine.

Seek urgent care for confusion, fainting, severe weakness, inability to keep fluids down, very little urine, severe abdominal or back pain, or yellowing of the eyes or skin. After heat exposure, worsening symptoms or altered alertness require immediate help. Dark urine with burning, fever, or flank pain also needs prompt review because infection or kidney involvement may be present.

Ask whether you need urine and blood tests, whether dehydration or heat exhaustion fits the pattern, and whether liver testing is appropriate. Tell the clinician when the colour began, how much you have been drinking, whether you exercised or overheated, and whether you noticed pain, fever, itching, or yellow skin.