Reye’s Syndrome

Reye’s Syndrome

Reye’s syndrome is a rare complication of common childhood respiratory infections, including chickenpox. Reye’s syndrome is most common in school-aged children and teenagers, but cases also occur in infants. The illness is rare in adults.


Reye’s syndrome should be suspected when vomiting begins three to seven days after the onset of a flu or chickenpox. Usually the vomiting becomes increasingly severe over a period of eight to 12 hours. When vomiting persists for more than 12 hours, or vomiting is associated with signs of brain disorder, such as staring spells, stupor, delirium or strange behaviour, call your doctor.

In the later stage of the disease, the child shows personality changes such as aggressive behaviour and disorientation. Other symptoms may include confusion, slurred speech, agitated delirium with screaming and struggling, and an inability to recognize parents. This stage is a medical emergency.

Although Reye’s syndrome can occur anytime, it is most frequent in January, February and March, in association with influenza and similar respiratory infections. About one-third of the cases of Reye’s syndrome occur as a complication of chickenpox, usually three or four days after the rash appears.

Vomiting on the first day of illness, especially when accompanied with diarrhea, is not typically due to Reye’s syndrome. In such cases, children are usually alert and active. They may be suffering from acute infectious gastroenteritis.


Diagnosis of Reye’s syndrome is based on a recent history of flu-like illness, persistent vomiting and blood tests. In the case of Reye’s syndrome, test results should show an elevation of serum alanine aminotransferase (ALT) levels with normal bilirubin levels. Other possible causes such as meningitis and encephalitis should also be excluded prior to making a final diagnosis.

Almost all cases of Reye’s syndrome have increased serum concentrations of certain liver enzymes such as ALT. Every hospital emergency room physician who evaluates children should be able to measure the ALT on an emergency basis.


When there is an elevation in serum ALT associated with unexplained vomiting, the child should be admitted to the hospital and treated with intravenous fluids. There is an excellent chance of recovery when Reye’s syndrome is diagnosed and treated early, before delirium or coma has developed. Children who are not diagnosed early may lapse into coma and die.


It is believed that aspirin may contribute to the development of Reye’s syndrome. Until conclusive evidence is obtained, doctors advise clients against the use of aspirin to treat chickenpox and during outbreaks of influenza-like disease. Acetaminophen is the preferred anti-fever medicine.

Many over-the-counter remedies contain aspirin (acetyl-salicylic acid), sodium or bismuth salicyclates. Consult with your pharmacist about a drug’s contents before giving it to your child.


National Help Line:
This support resource gives you and your loved one somewhere to turn for answers after diagnosis, helps you understand your disease, and provides you with the resources you need.  You can call 1 (800) 563-5483 Monday to Friday from 9 AM to 5 PM EST.

The Peer Support Network:
This is a national network of people living with liver disease that have offered to share their experiences with others. It was developed by the Canadian Liver Foundation as a means to link Canadians like you who have a family member who has liver disease, who care for someone who suffers from liver disease, or who have been diagnosed with a liver disease, to talk about your concerns with a peer in a similar situation.

If you would like to be connected with a peer supporter in your area, or would like to join the peer support network, please call the National Help Line at 1 (800) 563-5483 Monday to Friday from 9 AM to 5 PM EST or email us.

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