Acetaminophen is a pain reliever and fever reducer found in many over-the-counter (OTC) analgesics as well as prescription (Rx) products commonly prescribed at discharge from the emergency department. 1 An estimated 36% of Americans ingest acetaminophen at least once a month.1, 2 While acetaminophen is generally safe and effective when used at recommended doses, acetaminophen overdose has surpassed viral hepatitis as the leading cause of acute liver failure (ALF) in the United States.2-4 Moreover, one half to two-thirds of overdoses leading to acute liver failure are unintentional, suggesting the root cause may be poor understanding of medication labeling or failure to recognize the consequences of exceeding the recommended maximum daily dosage.2-4 On-going studies by this research group have shown patient misunderstanding of dosing instructions and warnings associated with OTC medicines to be prevalent.
It has also been suggested that patients receiving prescription medications containing acetaminophen may not be informed or aware of the potential risk of acetaminophen overuse when taking prescription products in combination with over-the-counter pain relievers.1 This is supported by the finding that a third of narcotic users were simultaneously using an OTC acetaminophen containing product in a multicenter study of ALF cases.2 To address the growing concern of acetaminophen misuse, in June 2009 the US Food and Drug Administration (FDA) convened a panel to discuss the maximum dose recommendations of acetaminophen found in OTC medications. The panel concluded that there was a notable lack of available evidence on consumer understanding and use of over-the-counter acetaminophen products. Studies are needed to explore patients' 1) knowledge of potential acetaminophen overdose when using prescription analgesics simultaneously with non-prescription acetaminophen and 2) avenues available to increase awareness of potential acetaminophen overdose from misuse of both OTC and Rx acetaminophen containing medicines.
