Systematic review on the use of activated charcoal for gastrointestinal decontamination following acute oral overdose.
Level 1 - systematic review of randomized trials
Systematic review synthesizing clinical, animal, and in vitro evidence
PubMed 34424785 · doi:10.1080/15563650.2021.1961144
What was done
A multi-society collaborative conducted a systematic review across seven databases (Medline, Embase, CINAHL, BIOSIS Previews, Web of Science, Scopus, Cochrane/DARE) from inception through December 31, 2019, with no language restrictions. The review investigated whether oral activated charcoal in adults or children prevents toxicity or improves clinical outcomes/survival compared to no charcoal, alongside evaluating pharmacokinetics, cathartic co-administration, and adverse events. Two authors independently assessed study quality and risk of bias using the GRADE methodology.
What was found
From 22,950 identified titles, 559 studies were included (296 human, 118 animal, and 145 in vitro), plus 71 human and two animal adverse event reports. Study quality was rated Low or Very Low GRADE in 469 studies (83%) and Moderate or High GRADE in 90 studies. Higher-grade data were concentrated in specific agents: paracetamol, phenobarbital, carbamazepine, cardiac glycosides, ethanol, iron, salicylates, theophylline, tricyclic antidepressants, and valproate. No studies evaluated optimal dosing for single- or multiple-dose charcoal. Clinical data showed the first charcoal dose was given beyond one hour in 97% of patients (n = 1,006), beyond two hours in 36% (n = 491), and beyond 12 hours in 4% (n = 43), whereas controlled studies administered charcoal within one hour in 48% (n = 2,359) and beyond two hours in 36% (n = 484). Across multiple scenarios, benefit was reported beyond one hour.
Why it matters
This review establishes the evidence base for revised clinical toxicology guidelines, demonstrating that activated charcoal administration may be beneficial beyond the historically rigid one-hour post-ingestion limit for certain poisonings.
Limits
The literature is dominated by low-quality evidence (83% Low or Very Low GRADE). Studies evaluating mixed or unknown ingestions were limited by low baseline rates of meaningful toxicity or death, and no comparative trials defined optimal dosing regimens for single-dose or multiple-dose activated charcoal.
Cited by
- partial Activated charcoal is an effective intervention for acute accidental poisoning by neutralizing and adsorbing ingested poisons.