A PROSPECTIVE EVALUATION OF THE EFFECT OF ACTIVATED-CHARCOAL BEFORE ORAL N-ACETYLCYSTEINE IN ACETAMINOPHEN OVERDOSE

Study objective: To evaluate whether activated charcoal (AC) reduces t he efficacy of subsequent oral N-acetocysteine therapy during acute ac etaminophen overdose. Design: Prospective observational case series of all acute acetaminophen overdoses reported to three certified regiona l poison centers. Types of patients: All patients with acute acetamino phen overdose in whom N-acetylcysteine therapy was initiated within 16 hours after ingestion. Interventions: 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. M easurements and results: One hundred twenty-two patients were evaluate d. Maximum recorded SGOT levels of more than 125 U/mL were defined as evidence of hepatotoxicity. AC was used in addition to N-acetylcystein e in 82 of 122 patients. Hepatotoxicity developed in four of 82 patien ts who received AC versus ten of 40 patients who did not receive AC (P < .005). An increasing dose of N-acetylcysteine provided no additiona l benefit (P > .05). Spacing the administration of AC and oral N-acety lcysteine less than or more than two ours apart did not affect outcome (P > .05). Conclusion: Administration of AC before the administration of oral N-acetylcysteine in acetaminophen overdose does not reduce th e 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 unwar ranted.