What should you know about dark urine after alcohol?

Alcohol can increase urination and make it easier to become dehydrated, especially when combined with heat, exercise, vomiting, or not eating and drinking normally. Concentrated urine may be deep yellow and have a stronger smell. Dark brown or tea-coloured urine is different and can occur with liver or bile problems, including hepatitis A or hepatitis B. Heat exhaustion can cause marked thirst, dizziness, headache, nausea, weakness, and heavy sweating. The colour alone cannot identify the cause.

Stop drinking alcohol while the change is being assessed. Sip water regularly, eat if you can, and use oral rehydration fluid when vomiting or heavy sweating has caused fluid loss. Avoid trying to correct the problem with more alcohol or unfamiliar supplements. Notice the timing, amount and colour of urine, and record vomiting, pain, fever, yellowing, or changes in alertness. If urine becomes lighter and you feel normal, continue sensible hydration; if it stays dark, contact a clinician.

Get urgent help for confusion, collapse, extreme drowsiness, repeated vomiting, inability to drink, very little urine, severe pain, or breathing difficulty. Seek prompt review for brown urine, yellow eyes or skin, pale stools, fever, upper abdominal pain, blood in urine, or darkening that persists after hydration.

Ask whether dehydration is enough to explain the colour, whether urine and blood tests are appropriate, and whether any medicines or liver symptoms change the urgency.