Reye’s Syndrome


What Is It?

Reye’s syndrome is a very rare disorder that damages many parts of the body, especially the brain and the liver. For reasons that are not yet clear, the parts of the cells that make energy (mitochondria) stop working correctly, affecting reactions throughout the body and causing severe illness. The most serious problems are swelling of the brain and problems with the breakdown of fat, which causes it to build up in the liver and other organs. The illness can be fatal, especially if not detected early and treated appropriately.

Although Reye’s syndrome can occur at any age, it is primarily a children’s disease, and most often affects children between the ages of 3 and 12.

Reye’s syndrome commonly occurs several days after recovering from a viral infection, such as the flu, common cold or chickenpox. It also can develop while the child is still sick, a few days after the viral illness began. While the exact cause of Reye’s syndrome is not known, researchers believe that in some cases it is caused by an abnormal response to aspirin or related products taken during a viral illness. For this reason, NEVER give aspirin to children with fever or a flulike illness.


Symptoms can include:

  • Frequent vomiting (every couple of hours over a day or two) that does not stop even when not eating or drinking
  • Extreme sleepiness (lethargy)
  • Confusion
  • Irritability and combativeness
  • Rapid breathing (hyperventilation)
  • Loss of consciousness
  • Seizures

In infants, the symptoms of Reye’s syndrome may not follow this typical pattern. For example, infants with Reye’s syndrome do not always vomit.


The doctor may suspect a child has Reye’s syndrome based on the symptoms and a history of very recent viral illness. Blood tests, including tests of liver function, will be done. Other tests often are necessary to confirm the diagnosis, including a biopsy of the liver (a small piece of the liver is removed and examined) and a lumbar puncture (spinal tap) to examine spinal fluid. Reye’s syndrome can be difficult to diagnose, and it is sometimes mistaken for other serious illnesses, such as encephalitis, meningitis, uncontrolled diabetes, or drug overdose.

Expected Duration

How long it takes to recover from Reye’s syndrome depends on how much the brain has swelled. People with mild disease usually recover quickly and completely.


Although a clear link between aspirin and Reye’s syndrome has not yet been proven, experts agree that to prevent Reye’s syndrome, the safest approach is NEVER to give aspirin or aspirin-containing medicines to children. Read labels carefully. Look for the word aspirin and other words that also mean aspirin: acetylsalicylate, acetylsalicylic acid, salicylic acid and salicylate. Non-aspirin medicines, such as acetaminophen (Tylenol), should be used instead.


Treatment depends on the symptoms but all patients with Reye’s syndrome require hospitalization and close monitoring. Successful management, which relies on early diagnosis, focuses on protecting the brain against irreversible damage by preventing or reducing brain swelling.

Specific treatments to protect the lungs and also reduce brain swelling may include:

  • Giving injecting fluids containing sugar and salts intravenously (into a vein)
  • Medications (for example, to decrease brain swelling or treat problems caused by liver failure)
  • Intubation (inserting a tube that helps with breathing)

Patients with more serious disease typically are treated in an intensive care unit.

When To Call A Professional

Reye’s syndrome is a serious, life-threatening condition. If your child has had a viral infection and has any symptoms of Reye’s syndrome, call your doctor immediately.


With early diagnosis and treatment, the chances of recovery are excellent. Some people will recover fully, while others may have permanent brain damage. The prognosis is poorer for people with Reye’s syndrome who rapidly become unconscious. If diagnosis and treatment are delayed, the chances for successful recovery and survival are less likely. If Reye’s syndrome is not treated, death is common, usually within a few days.

Johns Hopkins patient information

Last revised:

Diseases and Conditions Center

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All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.