Factors influencing the clinical efficacy of activated charcoal

The use of activated charcoal as part of the treatment of intoxicated patients has increased dramatically over the last ten years. Activated charcoal is currently suggested as therapy to prevent the absorption of orally ingested compounds, and is gaining popularity as a method of increasing systemic drug clearance. This review presents variables that should be considered when activated charcoal is used in the treatment of intoxicated patients. Variables that may alter the efficacy of charcoal therapy include the preparation and dose of charcoal used, the intoxicants involved, stomach contents, the gastrointestinal pH, concurrently administered materials, and time from toxin ingestion to charcoal administration. As a general guideline, a single, large dose should be administered with a cathartic as soon as possible after oral ingestion to prevent drug absorption. When charcoal is used to enhance systemic drug clearance, the dosage regimen should be individualized, based on the drugs involved and the patient's gastrointestinal tract function, fluid and electrolyte status, and the severity of intoxication.