TOXICITY FROM TEA INGESTION IN AN INFANT: A COMPUTER SIMULATION ANALYSIS

A seven week old previously healthy infant presented with tonic posturing and central nervous system irritability after concentrated tea ingestion. Using a gas chromatographic analysis technique, a sample of similarly prepared tea was examined for levels of caffeine, theophylline, and theobromine. Caffeine was the only xanthine found in the tea. A simulation of caffeine absorption and elimination was performed on a computer utilizing Euler's method on a three compartment model consisting of caffeine in the gut, in the body water, and caffeine excreted. Convulsions after caffeine administration have been reported at doses of 7 mg/kg. In our patient, the total estimated ingested dose of caffeine was 75 mg or 14.7 mg/kg with a maximum predicted blood level at 3 2/3 hours. A xanthine blood level from the infant at 5 hours was 1.1 mg/100 ml compared to a computer predicted value of 1.3 mg/100 ml. Computer simulation may be utilized to predict the pharmacologic course and distribution of ingested agents.