Formate concentrations in a case of methanol ingestion

An eight-month-old infant ingested at least 3.5 g of methanol when he accidentally received 5 mL of amoxicillin suspended in 70% methanol. The serum methanol concentration 8 h later was 9.7 mmol/L (310 mg/L) and the formate concentration 23 mmol/L (1.0 g/L). At 18 h after the ingestion, total CO2 had decreased to 6.8 mmol/L. Throughout the second day, 21-32 h after the ingestion, the methanol concentration was 2.8-3.4 mmol/L (90-110 mg/L) and that of formate was 31-33 mmol/L (1.4-1.5 g/L). On the third day, 46 h after the ingestion, methanol was not detected and the formate concentration had declined to 16 mmol/L (720 mg/L). The patient was treated with activated charcoal 7 h after the ingestion and with ethanol, administered both orally and intravenously, 21 h after the ingestion. No abnormalities of the infant's eyes were noted upon ophthalmological examination approximately 55 h after the incident.