Activated charcoal alone or after gastric lavage: a simulated large paracetamol intoxication

Abstract

Aims Activated charcoal is now being recommended for patients who have ingested potentially toxic amounts of a poison, where the ingested substance adsorbs to charcoal. Combination therapy with gastric lavage and activated charcoal is widely used, although clinical studies to date have not provided evidence of additional ef®cacy compared with the use of activated charcoal alone. There are also doubts regarding the ef®cacy of activated charcoal, when administered more than 1 h after the overdose. The aim of this study was to examine if there was a difference in the effect of the two interventions 1 h post ingestion, and to determine if activated charcoal was effective in reducing the systemic absorption of a drug, when administered 2 h post ingestion. Methods We performed a four-limbed randomized cross-over study in 12 volunteers, who 1 h after a standard meal ingested paracetamol 50 mg kg x1 in 125 mg tablets to mimic real-life, where several factors, such as food, interfere with gastric emptying and thus treatment. The interventions were activated charcoal after 1 h, combination therapy of gastric lavage followed by activated charcoal after 1 h, or activated charcoal after 2 h. Serum paracetamol concentrations were determined by h.p.l.c. Percentage reductions in the area under the curve (AUC) were used to estimate the ef®cacy of each intervention (paired observations). Results There was a signi®cant (P<0.005) reduction in the paracetamol AUC with activated charcoal at 1 h (median reduction 66%, 95% con®dence intervals 49, 76) compared with controls, and a signi®cant (P<0.01) reduction for gastric lavage followed by activated charcoal at 1 h (median reduction 48.2%, 95% con®dence interval 32.4, 63.7) compared with controls. There was no signi®-cant difference between the two interventions (95% con®dence interval for the difference x3.8, 34.0). Furthermore, we found a signi®cant (P<0.01) reduction in the paracetamol AUC when activated charcoal was administered 2 h after tablet ingestion when compared with controls (median 22.7%, 95% con®dence intervals 13.6±34.4). Conclusions These results suggest that combination treatment may be no better than activated charcoal alone in patients presenting early after large overdoses. The effect of activated charcoal given 2 h post ingestion is substantially less than at 1 h, emphasizing the importance of early intervention.

Acetaminophen Poisoning: an Evidence-Based Consensus Guideline for Out-of-Hospital Management

“…Six randomized controlled trials (level 1b) have investigated the efficacy of activated charcoal in reducing acetaminophen absorption in healthy volunteers receiving supratherapeutic, but nontoxic, doses of acetaminophen. In these studies, activated charcoal (50-60 g) reduced the serum acetaminophen AUC by 25-67% if given at 1 hour after ingestion (102)(103)(104)(105). Another study found that activated charcoal (1 g/kg) mixed with soda and given 15 minutes after simulated overdose reduced acetaminophen absorption by 74% (30).…”

Adsorption of Paracetamol and Acetylsalicylic Acid onto Commercial Activated Carbons

“…While activated carbon can be administered in single or multiple doses, multiple-dose treatment is recommended when the amount of drug ingested is life-threatening and its absorption into the gastrointestinal tract is slow. A single oral dose is used for an overdose of salicylate, paracetamol, anti-arrhythmic drugs, anticonvulsants and cyclic antidepressants; multiple oral doses are recommended for overdoses of phenobarbital, carbamazepine, dapsone, quinine and theophylline (Gaudreault 2005;Jones 2006;Jepsen and Ryana 2005;Riordan et al 2002a,b;Christophersen et al 2002). Activated carbons can obviate the need for invasive intracorporeal treatments such as gastric lavage, bowel irrigation, forced diuresis and haemodialysis, and do not cause side-effects other than vomiting or diarrhoea (Bradberry and Vale 1995).…”

Current and future directions in the treatment and prevention of drug-induced liver injury: a systematic review

“…[51] There are few apparent downsides to attempting to remove undigested pills after an APAP overdose, although the closer to the time of ingestion the better. [47, 52] [53, 54] Inducing vomiting using syrup of ipecac, however, is more controversial. [47, 52] [53, 54] Doing so is not recommended after salicylate overdose,[50] nor is it recommended if the patient presents for treatment several hours after APAP overdose.…”

“…[47, 52] [53, 54] Inducing vomiting using syrup of ipecac, however, is more controversial. [47, 52] [53, 54] Doing so is not recommended after salicylate overdose,[50] nor is it recommended if the patient presents for treatment several hours after APAP overdose. [47] In vitro data suggest that AC may deactivate NAC administered orally [55], however this has not been reproduced in vivo , and is considered inconsequential.…”