Medical Disclaimer: NAC dosing should be guided by the Rumack-Matthew nomogram and clinical assessment. Patients with hepatotoxicity risk factors may require extended NAC treatment. This calculator does not replace clinical judgment. All doses should be verified by a clinical pharmacist. Consult Poison Control (1-800-222-1222) for all acetaminophen overdose cases. Maximum weight for IV dosing calculations is typically capped at 100 kg per many protocols — verify your institutional guidelines.