<P> The toxic effects of salicylates have been described since at least 1877 . In 2004 more than 20,000 cases with 43 deaths were reported in the United States . About 1% of those with an acute overdose die while chronic overdoses may have worse outcomes . Older people are at higher risks of toxicity for any given dose . </P> <P> Aspirin overdose has potentially serious consequences, sometimes leading to significant morbidity and death . Patients with mild intoxication frequently have nausea and vomiting, abdominal pain, lethargy, ringing in the ears, and dizziness . More significant signs and symptoms occur in more severe poisonings and include high body temperature, fast breathing rate, respiratory alkalosis, metabolic acidosis, low blood potassium, low blood glucose, hallucinations, confusion, seizure, cerebral edema, and coma . The most common cause of death following an aspirin overdose is cardiopulmonary arrest usually due to pulmonary edema . </P> <Table> <Tr> <Th> Severity </Th> <Th> Mild (150 mg / kg) </Th> <Th> Moderate (150--300 mg / kg) </Th> <Th> Severe (300--500 mg / kg) </Th> </Tr> <Tr> <Th> Toxicity </Th> <Td> No toxicity expected </Td> <Td> Mild to moderate toxicity expected </Td> <Td> Life - threatening toxicity expected </Td> </Tr> <Tr> <Th> Symptoms </Th> <Td> Nausea, vomiting, dizziness </Td> <Td> Nausea, vomiting, ringing in the ears, headache, confusion, hyperventilation, tachycardia, fever </Td> <Td> Delirium, hallucinations, seizures, coma, respiratory arrest </Td> </Tr> </Table> <Tr> <Th> Severity </Th> <Th> Mild (150 mg / kg) </Th> <Th> Moderate (150--300 mg / kg) </Th> <Th> Severe (300--500 mg / kg) </Th> </Tr>

What dose of salicylate can cause severe toxicity in a patient