Reye syndrome
When aspirin is taken in children with a viral infection such as mononucleosis, it can lead to Reye syndrome, which is characterized by encephalopathy and hepatic damage. This syndrome causes lethargy, vomiting, hypersomnia, restlessness, delirium, hyperventilation, decorticate rigidity, coma, seizures, loss of reflexes, flaccid paralysis, respiratory arrest, dilated and fixed pupils, and eventually may lead to death.