What Is Reye Syndrome?

Reye syndrome is a rare but serious illness that can affect the brain and liver. It's most common in kids who are recovering from a viral infection.

It's still not well understood, but studies have linked it to the use of aspirin (salicylates) or aspirin products during illnesses caused by viruses.

In rare cases, it can cause death within hours. Because it can be a life-threatening disorder, Reye syndrome is a medical emergency.

Early detection and treatment are critical. The chances for a full recovery are best when Reye (pronounced: rye) syndrome is treated in its earliest stages.

Who Gets Reye Syndrome?

Reye (or Reye's) syndrome most often affects kids 4 to 14 years old. The number of cases has dropped greatly since doctors began advising against giving aspirin to kids and teens, especially during viral illnesses.

Most cases happen when viral diseases are epidemic, such as during the winter months or after an outbreak of chickenpox or the flu.

What Are the Signs & Symptoms Reye Syndrome?

The signs and symptoms of Reye syndrome almost always follow the start of a viral illness, such as an upper respiratory tract infection (a cold, the flu, etc.), a diarrheal illness, or chickenpox.

Reye syndrome can start from 1 day to 2 weeks after a viral infection. Symptoms include:

  • vomiting often
  • tiredness or sleepiness
  • in babies, diarrhea and rapid breathing
  • irritability or aggressive behavior

Other symptoms include changes in vision, trouble hearing, and abnormal speech. In the later stages, a child may:

  • behave irrationally
  • be confused
  • have severe muscle weakness, seizures, and loss of consciousness (pass out)

Even though it's rare, Reye syndrome should be considered if a child is vomiting a lot or shows a change in mental status or behavior, particularly after a recent viral illness.

How Is Reye Syndrome Treated?

Children with Reye syndrome are usually treated in a hospital. Those who are seriously ill will be cared for in the intensive care unit (ICU).

Treatment is supportive, as there is no cure. The clinical care team will:

  • Make sure the child stays hydrated and maintains electrolyte balance.
  • Check nutrition intake.
  • Watch the child's heart rate and breathing.
  • Watch the child's intracranial pressure (pressure of the fluid in the brain) and blood pressure.

Tests done can include blood tests to check electrolytes and liver function and an imaging study of the brain (CAT scan or MRI).

A child also might get:

  • small amounts of insulin to increase glucose metabolism
  • corticosteroids to reduce brain swelling
  • diuretics to get rid of excess fluid

If seizures happen, they'll be treated with medicines. Some kids might need breathing help from a breathing machine or respirator if their breathing gets too slow or ineffective.

The outlook for children with Reye syndrome has improved thanks to earlier diagnosis and better treatment. If the late stages of the syndrome happen, they can cause brain damage, disability, or death.

When Should I Call the Doctor?

Call your doctor or get medical help right away if your child:

  • is vomiting a lot
  • has behavioral changes
  • is much sleepier than usual

This is even more important if your child has had a recent viral illness, such as the flu or a cold.

Of course, many kids with viruses will have some of these symptoms, and most will not have Reye syndrome. But it's best to be sure because early diagnosis is the key to successful treatment of Reye syndrome.

How Can Parents Help Prevent Reye Syndrome?

Never use aspirin or other drugs from the salicylate (suh-LISS-uh-late) family to treat chickenpox, the flu, or any other viral diseases. Many over-the-counter (OTC) medicines contain salicylates, including bismuth subsalicylate (for instance, Pepto-Bismol). Be sure to read the labels and talk to your health care provider if you're not sure whether a medicine is safe for your child.

In general, kids and teens should not take aspirin (salicylates) except on the advice of a doctor for certain conditions.

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