What are the first signs of rhabdomyolysis?

Rhabdomyolysis happens when damaged muscle releases substances into the bloodstream that can strain the kidneys and disturb body chemistry. Symptoms may affect the muscles used during intense exercise, but they can also follow a crush injury, heat illness, prolonged immobility, or certain medicines. Ordinary muscle soreness after exercise usually follows a familiar workload and improves gradually; severe pain, pronounced weakness, swelling, or urine changes are different warning signs. Not everyone has every symptom.

Stop strenuous exercise and do not attempt to train through severe muscle pain or weakness. Move to a cool place if heat was involved, and take small drinks only if you are alert and able to swallow normally. Contact urgent medical services or an emergency department for assessment; clinicians may check blood and urine and monitor kidney function. Do not self-treat with leftover medicines.

Seek emergency care immediately for dark tea-coloured urine, very little urine, worsening weakness, confusion, fainting, breathing difficulty, severe swelling, or muscle pain that is out of proportion to the activity. Also seek urgent assessment after a major injury or heat illness, even if symptoms seem limited at first.

Tell the team what exercise, injury, heat exposure, or medicine preceded the symptoms. Ask which tests are needed, how much activity and fluid intake are appropriate for you, and which warning signs should bring you back for care.