Treatment of APAP Toxicity With IV and Oral NAC 2008-2011

Inclusion Criteria: * Admitted to CHMCA between June 1, 2008 to June 30, 2011 * Qualifying ICD-9 diagnosis code for the following APAP overdose situations: poisoning, accidental, suicide attempt, therapeutic use, assault, and undetermined (965.4, E850.4, E950.0, E935.4, E962.0, E980.0) * Serum APAP concentration above the possible hepatotoxic line on the Rumack-Matthew's nomogram if obtained \> 4 hours post ingestion * Between ages 0-21 years on date of admission * Acute APAP ingestion Exclusion Criteria: * Serum APAP concentrations not actually documented * Did not receive the oral or IV NAC treatment * Preexisting liver disease such as cirrhosis or hepatitis C * Patient \> 21 years of age on the date of admission * Chronic APAP ingestion