What should you know about dark urine after waking up?

Urine becomes more concentrated while you sleep because you are not drinking. A strong yellow colour that lightens after normal morning fluids can fit this pattern. Colour can also change with foods, vitamins, medicines, or blood. Brown, tea-coloured, or cola-coloured urine is different from ordinary morning concentration, particularly when it comes with yellow eyes, pale stools, itching, nausea, swelling, or pain. Burning, urgency, fever, or lower abdominal discomfort may suggest a urinary problem. A single observation is less informative than the shade, amount, and whether it returns later in the day.

Notice the colour before flushing, then drink normally and see whether later urine becomes lighter. Do not force fluids if you have heart, kidney, or liver disease or have been given a fluid limit. Check recent vitamins, medicines, and foods that may alter colour, and record when the change began. If the urine remains dark through the day or recurs on several mornings, book a medical appointment. A clinician may use a urine sample and blood tests to look for blood, infection, kidney changes, or liver-related causes.

Seek urgent care if you cannot pass urine, feel faint or confused, have severe side or abdominal pain, repeated vomiting, marked weakness, or see obvious blood or cola-coloured urine. Contact a clinician promptly for yellow skin or eyes, fever with urinary symptoms, swelling, or dark urine that does not lighten after ordinary drinking. Do not wait for repeated mornings when the urine is brown or your general condition is worsening.

Ask whether your morning pattern fits concentration, whether your medicines or supplements can change urine colour, and whether urine, kidney, or liver tests are appropriate. Mention thirst, snoring or mouth-breathing, overnight sweating, pain, fever, and changes in urine volume.