Intravenous acetaminophen associated with acute liver failure.

A woman in her mid-60s, without known liver disease, was admitted to the hospital with a partial malignant colonic obstruction. Over a 6-day course, she received a total of 13 g of intravenous acetaminophen not exceeding 4 g over a 24-hour period. She developed encephalopathy and an international normalised ratio of 6.1 meeting criteria for acute liver failure (ALF). She was treated with intravenous N-acetyl cysteine and other causes of liver failure were excluded. The patient was discharged with subsequent resolution of encephalopathy and improvement of her liver chemistries. Though ALF is rare, in countries where acetaminophen is readily available, almost 50% of ALF cases are acetaminophen-induced hepatotoxicity and most have been documented as oral ingestion of acetaminophen. We present a rare case of intravenous acetaminophen-induced ALF.