title: A prospective evaluation of the effect of activated charcoal before oral N-acetylcysteine in acetaminophen overdose.
abstract: OBJECTIVE
  To evaluate whether activated charcoal (AC) reduces the efficacy of subsequent oral N-acetylcysteine therapy during acute acetaminophen overdose.
  
  
  METHODS
  Prospective observational case series of all acute acetaminophen overdoses reported to three certified regional poison centers. TYPES OF PATIENTS: All patients with acute acetaminophen overdose in whom N-acetylcysteine therapy was initiated within 16 hours after ingestion.
  
  
  METHODS
  All patients were treated with oral N-acetylcysteine therapy for 72 hours. The decision to use AC was left to the treating physician without input from the investigator.
  
  
  RESULTS
  One hundred twenty-two patients were evaluated. Maximum recorded SGOT levels of more than 125 U/mL were defined as evidence of hepatotoxicity. AC was used in addition to N-acetylcysteine in 82 of 122 patients. Hepatotoxicity developed in four of 82 patients who received AC versus ten of 40 patients who did not receive AC (P < .005). An increasing dose of N-acetylcysteine provided no additional benefit (P > .05). Spacing the administration of AC and oral N-acetylcysteine less than or more than two hours apart did not affect outcome (P > .05).
  
  
  CONCLUSIONS
  Administration of AC before the administration of oral N-acetylcysteine in acetaminophen overdose does not reduce the efficacy of N-acetylcysteine therapy and may provide some additional hepatoprotective benefit. The practice of increasing the dose of oral N-acetylcysteine therapy after the administration of AC appears unwarranted.
authors.affiliation: Poison Center, Philadelphia, Pennsylvania.
authors.forename: H A
authors.initials: HA
authors.lastname: Spiller
authors.forename: E P
authors.initials: EP
authors.lastname: Krenzelok
authors.forename: G A
authors.initials: GA
authors.lastname: Grande
authors.forename: E F
authors.initials: EF
authors.lastname: Safir
authors.forename: J J
authors.initials: JJ
authors.lastname: Diamond
mesh_terms: D000082:Acetaminophen / Q000506:poisoning*; D000111:Acetylcysteine / Q000627:therapeutic use*; D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002606:Charcoal / Q000494:pharmacology / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D062787:Drug Overdose / Q000628:therapy; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D016896:Treatment Outcome
chemical_list: D002606:Charcoal; D000082:Acetaminophen; D000111:Acetylcysteine