What is rhabdomyolysis?

Rhabdomyolysis is a condition that can result when injured muscle cells release their contents into the bloodstream.

How does it occur?

Rhabdomyolysis usually happens when you injure your muscles by exercising much more than usual. It could happen from weightlifting, running, job training (such as for fire crews or in military boot camp), or football practice.

Other possible causes are:

• bad injuries, such as when your muscles are crushed

• heat reactions (for example, when you exercise in hot, humid weather)

• not drinking enough fluids

• use of cocaine or alcohol or other drugs, including some prescribed medications

• inherited problems such as sickle cell anemia

• infection.

The injury to the muscles and release of chemicals by injured muscle cells can cause severe problems.

• The chemicals released by the muscle cells enter the bloodstream and flow to the kidneys, where they can do temporary or permanent damage. The damage may cause your kidneys to stop working.

• If there is a lot of muscle swelling from the injury, the swelling can become so great that it cuts off circulation to the affected part of your body (for example, your forearm or the calf of your leg). It may also permanently damage nerves in the swollen area. This is called compartment syndrome.

• Sometimes, but rarely, when the kidneys begin to fail the blood may stop clotting normally. This may happen because of all the complex changes in the blood after the release of chemicals from the muscle cells.

What are the symptoms?

The most common symptoms are:

• muscle pain

• weakness

• brown or bloody-looking urine.

Other symptoms are:

• muscle swelling

• nausea

• back pain.

How is it diagnosed?

Your health care provider will:

• Ask about your symptoms.

• Examine you, especially the areas where you have pain.

• Ask if you have overexerted or injured yourself recently.

• Do lab tests of your urine and blood.

What is the treatment?

• The most important part of treatment is getting more fluids into your body. You may be given fluids by mouth or intravenously (IV).

• You may need to spend some time in the hospital.

• Your health care provider will check how well your kidneys are working. In a very severe case, you may have kidney failure and need dialysis (using a machine to do what your kidneys normally do).

• Your health care provider will check for development of compartment syndrome. If you have compartment syndrome, it may first be treated with rest and cold packs. If it does not get better, you may need surgery to relieve the pressure. This usually involves making shallow cuts in the skin and tissue over the muscle. (Before the surgery you are given an anesthetic to numb the area.)

What can I do to help prevent rhabdomyolysis?

To help prevent rhabdomyolysis:

• Exercise wisely. A good rule of thumb is never to increase your workout more than 10% a week. For example, don't increase the miles you run, the weights you lift, or the number of times you do an exercise more than 10%. When it's hot and humid, don't increase your activity by even this much.

• During exercise, drink plenty of fluids. Drink even more when it is hot and humid.

If you do develop rhabdomyolysis, you can help prevent complications by seeing your health care provider right away. Call your provider if after a long workout or serious injury you have:

• severe muscle pain with swelling

• weakness that doesn't go away

• dark urine.