Paracetamol Dosing Errors in People Aged 12 Years and Over: An Analysis of Over 14,000 Cases Reported to an Australian Poisons Information Centre.

Abstract

Paracetamol dosing errors can cause acute liver injury, with potentially toxic doses only slightly above the therapeutic range. This study aimed to characterise unintentional paracetamol overdose reported to an Australian poisons centre, including time trends, demographics, types of dosing errors, and outcomes. Records regarding paracetamol dosing errors for individuals aged ≥12 years were extracted from the New South Wales Poisons Information Centre database, January 2017 to June 2023. Data from 2021 underwent an in-depth screening of free text case notes to examine: dose, duration, products involved, reasons for ingestion and outcomes including hospitalisation, treatment, liver transplantations and deaths. Where possible, complete outcome data were obtained from medical records of New South Wales hospitalised cases in 2021. There were 14,380 exposures due to paracetamol dosing errors (predominantly self-administered, median age 43 years, 62.6% female), with an average yearly increase of 2.5% (95% CI 1.6-3.8%; p < 0.0001). The in-depth analysis of exposures recorded during 2021 revealed 1899 exposures (median age 46 years, 63.4% female) with 26.8% requiring hospitalisation. Immediate- and modified-release formulations were highly implicated. Multiple paracetamol-containing products were ingested in approximately 20% of exposures. Hospitalised exposures were associated with paracetamol use for dental pain and ingested higher doses for longer durations. Over half of those hospitalised (52%) were treated with the antidote (N-acetylcysteine), and 6% of exposures developed hepatotoxicity. Paracetamol dosing errors continue to occur, with relatively high rates of hospitalisation and liver injury. Many hospitalisations involved use for dental pain. Possible preventative measures include ingredient name prominence and increased education on appropriate dosing.