Acetaminophen overdose is a common and potentially life-threatening cause of acute liver injury. While intentional overdoses are widely acknowledged, occult overdoses often remain overlooked, especially in vulnerable populations such as older adults. This can be associated with a significant risk of clinical deterioration due to delayed diagnosis and timely delivery of antidote treatment. We present the case of a 68-year-old man who unknowingly consumed supratherapeutic doses of acetaminophen, unaware of the drug’s potential for harm. This led to a high anion gap metabolic acidosis, multiple organ failure, including encephalopathy and severe hepatotoxicity. This case emphasizes the critical need to consider acetaminophen toxicity in patients with altered mental status and highlights the importance of early recognition, timely initiation of N-acetylcysteine therapy, and increased vigilance in elderly patients and patients who present with altered mental status or unexplained high anion gap metabolic acidosis.
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