Getting the Knack of NAC

A 46-year-old woman with a history of Crohn’s disease presents with encephalopathy. She is somnolent and unable to follow commands. Her exam is notable for scleral icterus and RUQ tenderness. Labs show AST 3,694 IU/L, ALT 6,158 IU/L, International Normalized Ratio (INR) 2.1, and total bilirubin 6.6 mg/dL. Her acetaminophen level is 46 mcg/mL; the timing of her ingestion is not clear.

What is the most appropriate treatment for this patient?