Rhabdomyolysis and a swollen arm

Rhabdomyolysis can affect the muscles of the upper arm or forearm after heavy exertion, direct injury, prolonged compression, heat illness, or another trigger. Damaged tissue draws in fluid and may make the arm feel firm, tight, or painful. Weak grip, difficulty bending or straightening the elbow, altered sensation, or pain that keeps increasing is more concerning than mild soreness after activity. Other causes, including a fracture, tendon injury, infection, or a blood-vessel problem, can also swell an arm, so examination is needed.

Remove rings, watches, and tight sleeves before swelling increases. Rest the arm and seek prompt medical advice; do not exercise it, apply forceful massage, or tightly wrap it. Keep a note of when swelling began, whether it followed lifting or an injury, changes in urine, and any medicines or supplements. A healthcare professional may assess circulation, strength, sensation, arm pressure, urine, muscle-injury markers, kidney function, and electrolytes.

Seek emergency care if the arm becomes rapidly larger, extremely tight, pale, blue, cool, numb, or difficult to move, or if pain is severe and escalating. Dark or very little urine, marked weakness, dizziness, confusion, breathing difficulty, or vomiting also require urgent attention. These signs can reflect dangerous pressure in the limb or broader muscle and kidney complications.

Is circulation and nerve function in my arm normal? Could this be muscle breakdown or pressure within the limb? Which tests are needed? Should I avoid particular medicines or activities while it heals?