Common causes include muscle injury and impaired blood flow in damaged tissue, medications, toxic substances, and infections.
Less common causes include electrolyte imbalances, endocrine and genetic disorders, extreme exercise, and extremes in body temperature.
Symptoms can include muscle pain, weakness, and reddish-brown (or tea-colored) urine, but few people have all of these symptoms.
Serious complications include acute kidney injury Acute Kidney Injury Acute kidney injury is a rapid (days to weeks) decline in the kidneys’ ability to filter metabolic waste products from the blood. Causes include conditions that decrease blood flow to the kidneys... read more (also called acute kidney failure).
Diagnosis is with blood and urine tests.
Treatments are aimed at the cause and any resulting complications (for example, acute kidney injury is treated with intravenous fluids and sometimes dialysis Dialysis Dialysis is an artificial process for removing waste products and excess fluids from the body, a process that is needed when the kidneys are not functioning properly. There are a number of reasons... read more
).
(See also Overview of Kidney Failure Overview of Kidney Failure Kidney failure is the inability of the kidneys to adequately filter metabolic waste products from the blood. Kidney failure has many possible causes. Some lead to a rapid decline in kidney function... read more .)
Normal skeletal muscle function requires proper exchange of electrolytes (electrically charged minerals such as sodium and potassium) across muscle cells (myocytes). This exchange allows the cells to adequately metabolize adenosine triphosphate (ATP), a molecule necessary for transporting energy within cells and powering the body’s functions.
In rhabdomyolysis the processes that support the normal functioning of skeletal muscle are disrupted, so that myocytes break down and release some of their contents into the bloodstream, including
Creatine kinase (CK), a protein that rises when muscle is damaged
Myoglobin, an iron-containing protein that transports and stores oxygen in myocytes
Electrolytes
When the kidneys are functioning normally, they filter all myoglobin and excess creatine kinase out of the bloodstream through urination. High concentrations of myoglobin in the blood can overwhelm and damage the kidneys (causing acute kidney injury Acute Kidney Injury Acute kidney injury is a rapid (days to weeks) decline in the kidneys’ ability to filter metabolic waste products from the blood. Causes include conditions that decrease blood flow to the kidneys... read more ) and other organs.
Any form of muscle damage can result in rhabdomyolysis. The most common causes of that damage include
Direct injury of the muscle or impairment of blood flow in muscle tissue, such as occurs in crush injuries, electric shocks Electrical Injuries An electrical injury occurs when a current passes through the body, interfering with the function of an internal organ or sometimes burning tissue. Often the main symptom is a skin burn, but... read more , seizures Seizure Disorders In seizure disorders, the brain's electrical activity is periodically disturbed, resulting in some degree of temporary brain dysfunction. Many people have unusual sensations just before a seizure... read more , or compartment syndrome Compartment Syndrome Compartment syndrome is increased pressure in the space around certain muscles. It occurs when injured muscles swell so much that they cut off their blood supply. Pain in the injured limb increases... read more (a painful condition characterized by dangerously high levels of pressure in the affected muscle)
Some medications and toxic substances
Infection (for example, influenza A or B Influenza (Flu) Influenza (flu) is a viral infection of the lungs and airways with one of the influenza viruses. It causes a fever, runny nose, sore throat, cough, headache, muscle aches (myalgias), and a general... read more virus, coxsackievirus Overview of Enterovirus Infections Enteroviruses are a group of viruses. Enterovirus infections affect many parts of the body and may be caused by any of several different viral strains. Enterovirus infections may be caused by... read more
, or the bacteria Staphylococcus aureus Staphylococcus aureus Infections Staphylococcus aureus is the most dangerous of all of the many common staphylococcal bacteria. These gram-positive, sphere-shaped (coccal) bacteria (see figure ) often cause skin infections... read more 
)
Some medications and toxic substances (for example, statins Lipid-Lowering Drugs 
) can cause direct muscle damage. Other medications and toxic substances raise levels of medications that could damage muscle (for example, drug interactions involving antibiotics Overview of Antibiotics Antibiotics are drugs used to treat bacterial infections. They are not effective against viral infections and most other infections. Antibiotics either kill bacteria or stop them from reproducing... read more ). Still other medications and toxic substances damage muscle indirectly by restricting blood supply to those muscles. For example, people who are sedated and immobile after taking medications such as antianxiety agents Misuse of Antianxiety Medications and Sedatives Antianxiety and sedative medications are prescription drugs used to relieve anxiety and/or help with sleep, but their use can result in dependency and a substance use disorder. Using prescription... read more , antipsychotics Antipsychotic Drugs Psychosis refers to symptoms such as delusions, hallucinations, disorganized thinking and speech, and bizarre and inappropriate motor behavior that indicate loss of contact with reality. A number... read more , cocaine Cocaine Cocaine is an addictive stimulant drug made from leaves of the coca plant. Cocaine is a strong stimulant that increases alertness, causes euphoria, and makes people feel powerful. High doses... read more , amphetamines Amphetamines Amphetamines are stimulant drugs that are used to treat certain medical conditions but are also subject to abuse. Amphetamines increase alertness, enhance physical performance, and produce euphoria... read more , or alcohol Alcohol Use Alcohol (ethanol) is a depressant (it slows down brain and nervous system functioning). Consuming large amounts rapidly or regularly can cause health problems, including organ damage, coma,... read more may stay in the same position for hours, which can lead to compression and damage of certain muscles and the blood vessels to those muscles.
Less common causes of rhabdomyolysis include
Electrolyte disorders (for example, low blood levels of potassium [ hypokalemia Hypokalemia (Low Level of Potassium in the Blood) In hypokalemia, the level of potassium in blood is too low. A low potassium level has many causes but usually results from vomiting, diarrhea, adrenal gland disorders, or use of diuretics. A... read more ] or phosphate [ hypophosphatemia Hypophosphatemia (Low Level of Phosphate in the Blood) In hypophosphatemia, the level of phosphate in blood is too low. (See also Overview of Electrolytes and Overview of Phosphate's Role in the Body.) Phosphate is one of the body's electrolytes... read more ])
Genetic disorders (for example, Duchenne muscular dystrophy Duchenne Muscular Dystrophy and Becker Muscular Dystrophy Muscular dystrophies are a group of inherited muscle disorders in which one or more genes needed for normal muscle structure and function are defective, leading to muscle weakness of varying... read more or Becker muscular dystrophy Duchenne Muscular Dystrophy and Becker Muscular Dystrophy Muscular dystrophies are a group of inherited muscle disorders in which one or more genes needed for normal muscle structure and function are defective, leading to muscle weakness of varying... read more )
Extreme exercise
Prolonged bed rest
Extremes in body temperature (for example, hypothermia Hypothermia Hypothermia (dangerously low body temperature) is often regarded as a cold injury, because it can be caused or made worse by exposure to cold surroundings. Being in an environment that is too... read more [low body temperature]; and disorders accompanied by hyperthermia [high body temperatures], such as neuroleptic malignant syndrome Neuroleptic Malignant Syndrome Neuroleptic malignant syndrome is confusion or unresponsiveness, muscle rigidity, high body temperature, and other symptoms that occur when certain antipsychotic (neuroleptic) drugs or anti-vomiting... read more , malignant hyperthermia Malignant Hyperthermia Malignant hyperthermia is a rare, life-threatening rise in body temperature that occurs in susceptible people who are given certain muscle-relaxing drugs plus an anesthetic gas for surgery.... read more , and heatstroke Heatstroke Heatstroke is a life-threatening condition that results in very high body temperature and malfunction of many organ systems, which may be fatal. (See also Overview of Heat Disorders.) Heatstroke... read more )
Symptoms of Rhabdomyolysis
The 3 classic symptoms of rhabdomyolysis are muscle pain, weakness, and reddish-brown or tea-colored urine (caused by high levels of the red-pigmented protein myoglobin in the blood). However, this trio of symptoms is present in less than 10% of all people with rhabdomyolysis.
The symptoms of rhabdomyolysis vary, and many people have no muscle complaints at all. When present, muscle pain tends to affect the shoulders, thighs, lower back, and calves.
Other signs and symptoms depend on the cause of the original muscle injury as well as on the complications of that injury (for example, fever in people with infection or changes in alertness in intoxicated people).
Acute kidney injury Acute Kidney Injury Acute kidney injury is a rapid (days to weeks) decline in the kidneys’ ability to filter metabolic waste products from the blood. Causes include conditions that decrease blood flow to the kidneys... read more is very common, occurring in 15 to 50% of people who have rhabdomyolysis complications. Occasionally, rhabdomyolysis is complicated by disseminated intravascular coagulation Disseminated Intravascular Coagulation (DIC) Disseminated intravascular coagulation is a condition in which small blood clots develop throughout the bloodstream, blocking small blood vessels. The increased clotting depletes the platelets... read more , the presence of small blood clots in blood vessels throughout the body.
Diagnosis of Rhabdomyolysis
A doctor’s evaluation
Blood and urine tests
Doctors suspect rhabdomyolysis based on symptoms. The diagnosis is confirmed by blood tests.
Sometimes additional laboratory testing to detect myoglobin in the urine is done to confirm the diagnosis.
Treatment of Rhabdomyolysis
Treatment of underlying cause
Treatment of complications
In general, treatment is aimed at the cause and any complications of rhabdomyolysis.
Such treatment typically includes intravenous fluids to prevent and treat acute kidney injury Acute Kidney Injury Acute kidney injury is a rapid (days to weeks) decline in the kidneys’ ability to filter metabolic waste products from the blood. Causes include conditions that decrease blood flow to the kidneys... read more .
If compartment syndrome Compartment Syndrome Compartment syndrome is increased pressure in the space around certain muscles. It occurs when injured muscles swell so much that they cut off their blood supply. Pain in the injured limb increases... read more is the cause of the rhabdomyolysis, a surgical procedure called a fasciotomy is done to relieve pressure in the muscle. Relieving this pressure helps to reestablish healthy circulation in the affected tissue. Infections are treated with the appropriate medications. Any medications suspected of causing the rhabdomyolysis (for example, statins) are stopped. Electrolyte disturbances Overview of Electrolytes More than half of a person's body weight is water. Doctors think about water in the body as being restricted to various spaces, called fluid compartments. The three main compartments are Fluid... read more are corrected.
Acute kidney injury may require hemodialysis Dialysis Dialysis is an artificial process for removing waste products and excess fluids from the body, a process that is needed when the kidneys are not functioning properly. There are a number of reasons... read more . Disseminated intravascular coagulation Disseminated Intravascular Coagulation (DIC) Disseminated intravascular coagulation is a condition in which small blood clots develop throughout the bloodstream, blocking small blood vessels. The increased clotting depletes the platelets... read more is treated with fresh frozen plasma Plasma People are sometimes given transfusions of whole blood during severe bleeding (for example after an injury or pregnancy complications), but usually they are given only the blood component they... read more 
.
