What should you know about severe muscle pain and dark urine?

Dark urine may reflect concentrated urine from dehydration, but it can also contain pigment released when muscle cells are damaged. This can happen after unusually strenuous activity, prolonged heat exposure, injury, or some medicines. Liver conditions can darken urine too, especially with yellowing of the eyes or skin, pale stools, nausea, or discomfort under the right ribs. Urine colour alone cannot identify the cause, so a clinician may need to assess your muscles, hydration, kidney function, and liver-related symptoms.

Stop strenuous activity and move to a cool place if heat played a part. Sip water if you are awake, able to drink, and not on a fluid restriction. Do not exercise through the pain, take leftover medicines, or rely on colour returning to normal. Note when the pain and urine change began, recent exertion, heat exposure, vomiting or diarrhoea, injuries, and every medicine or supplement you use.

Contact urgent medical services promptly rather than waiting for the symptom to pass. Go urgently if pain is severe or spreading, urine output falls, you feel faint or confused, you cannot keep fluids down, you have marked weakness, swelling, fever, or yellow skin or eyes. After heat exposure, headache, dizziness, heavy sweating followed by reduced sweating, or collapse raises the urgency.

Ask which tests are needed to check muscle injury, kidney function, hydration, and liver health. Tell the clinician about new exercise, heat exposure, injuries, recent illness, alcohol, and medicines that may affect muscles or urine.