Reye syndrome
Background
Reye syndrome is a rare sudden acute illness involving mainly the liver and brain, which affects children and, occasionally, adults when they appear to be recovering from a viral illness - typically, but not exclusively, influenza or chicken pox.
There is substantial evidence that aspirin, given for the viral illness symptoms, initiates the onset of the syndrome in most (but possibly not all) cases. From June 1986 all aspirin containing medications in the UK were required to carry warning labelling cautioning against their use in children under twelve years except on medical advice. In April 2003 the Medicines and Healthcare Products Regulatory Agency issued new advice that would be applicable to all UK products containing aspirin from October 2003. This stated that the warning should now say: 'Do not give to children under sixteen years unless on the advice of a doctor.' Since these warnings were issued the incidence of Reye syndrome has declined dramatically.
Some rare inherited metabolic diseases such as Medium Chain Acyl Co - enzyme Dehydrogenase Deficiency (MCAD see Metabolic diseases) may cause illnesses which are very similar to Reye syndrome.