HOW LONG AFTER DRUG INGESTION IS ACTIVATED CHARCOAL STILL EFFECTIVE?

Background: In the recent AACT/EAPCCT position statement on activated charcoal it was stated that 'there are insufficient data to support or exclude its use after 1 hour of ingestion.' The purpose of this study was to determine the effectiveness of activated charcoal administered 1, 2, and 3 hours after drug ingestion. Methods: This was an IRB approved, human volunteer, randomized crossover study. Ten volunteers ingested 4.0 g of acetaminophen on four occasions at least one week apart. One ingestion served as a control and the other three as experimental ingestions with charcoal being administered at 1, 2, and 3 hours after acetaminophen dosing. Eight blood specimens were obtained over the initial 8 hours for serum acetaminophen concentrations (HPLC) which were used for calculation of routine pharmacokinetic parameters. Repeated measures ANOVA and Tukey's HSD test were used for statistical analysis. Results: Pharmacokinetic parameters for acetaminophen in our volunteers were consistent with literature values. The mean AUC [+ or -] SD for the control and the 1, 2, and 3 hour groups were 221 [+ or -] 54, 154 [+ or -] 71,206 [+ or -] 67, and 204 [+ or -] 58 mg/L.hr, respectively. The one hour group was the only one differing from control (p [is less than] 0.01). The decrease of bioavailibility at one hour was 30.3% which is similar to previous studies. Conclusion: Our data do not support the administration of activated charcoal at 2 hours or longer after drug overdose.
Tenenbein M, Green R, Grierson R, Sitar DS. University of Manitoba, Winnipeg, Manitoba, [...]