Rhabdomyolysis and clear urine: what to know

Rhabdomyolysis happens when damaged muscle releases substances into the bloodstream. Dark, tea-coloured or reddish-brown urine may occur when muscle pigment reaches the urine, but not everyone develops this change. Hydration, the timing of the sample and the amount of muscle injury can affect appearance. Severe muscle pain, unusual weakness, swelling or reduced urination deserve more attention than colour alone.

Stop strenuous activity and arrange prompt medical advice if symptoms followed intense exercise, a crush injury, prolonged immobility, heat exposure or another muscle stress. A clinician may check blood markers of muscle injury, kidney function, electrolytes and a urine sample. Do not try to diagnose the condition by repeatedly inspecting urine, and do not take extra medicines or supplements without advice.

Seek urgent care for severe or worsening muscle pain, marked weakness, confusion, fainting, vomiting, trouble breathing, swelling that feels tight, or much less urine than usual. These signs can accompany complications involving fluid balance, heart rhythm or kidney function. If symptoms are sudden or severe, use emergency services rather than driving yourself.

Ask which tests are needed, whether exercise or a medicine could have triggered the muscle injury, how much fluid is safe for you, and which symptoms should prompt immediate reassessment. Mention when the symptoms began, any recent exertion or injury, and all medicines and supplements you use.