HOW
LONG AFTER DRUG INGESTION IS ACTIVATED CHARCOAL STILL EFFECTIVE?
Green
R, et al. J Toxicol Clin Toxicol 2001;39(6):601-5.
OBJECTIVE:
The recent American Academy of Clinical Toxicology/European Association of
Poisons Centres and Clinical Toxicologists position statement on activated
charcoal stated "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 a human volunteer, randomized crossover study. Ten volunteers ingested
4 g of acetaminophen on four occasions at least 1 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 that were used for calculation of routine
pharmacokinetic parameters. Repeated measures of 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 area under the curve (AUC+/-SD) for the
control and the 1-, 2-, and 3-hour groups were 221 +/- 54, 154 +/- 71, 206 +/-
67 and 204 +/- 58 mg/L/h, respectively. The 1-hour group was the only one
differing from control (p < 0.01). The decrease of bioavailability at 1 hour
was 30.3%, which is similar to previous studies.
CONCLUSION:
Our data do not support the administration of activated charcoal as a
gastrointestinal decontamination strategy beyond 1 hour after drug overdose.