Introduction: In 2015, Australia and New Zealand treatment guidelines recommended a 2 h paracetamol serum concentration for risk assessment of unintentional paracetamol liquid exposures. We assess our experience with this approach. Methods: Retrospective case review of children <6 years-old with liquid paracetamol overdoses referred to a regional poisons information centre January 2017 to August 2022. We extracted data on the exposure and management from the poisons information centre and hospital medical records. We identified additional cases with two paracetamol concentrations obtained from September 2022 to June 2024. Results: Of 437 paediatric poisonings, 271 were eligible for inclusion. The median age was 24 months, the median time to presentation was 120 min, and paracetamol was the sole ingestant in 92% of cases. Blood testing was recommended in 131 patients (48.3%), occurring at 2 h post-ingestion in 62 patients (47.3%). Testing at a later time was mostly due to delayed presentation, including to hospitals unable to measure paracetamol concentrations. Eighteen patients (16.7%) had repeat blood testing, and five additional cases were identified in the subsequent period. Overall, the concentration decreased in 19 patients (83%), but in three patients it increased, from 73 mg/L to 81 mg/L (0.49-0.54 mmol/L), from 154 mg/L to 179 mg/L (1.03-1.19 mmol/L), and from 56 mg/L to 115 mg/L (0.37-0.77 mmol/L. Symptomatic patients were more likely to receive a second blood test or acetylcysteine while awaiting investigations. Of 19 patients administered acetylcysteine, it was discontinued in five due to low paracetamol serum concentrations. All patients recovered. Discussion: Guidelines were followed in >90% of patients and this testing regimen shortened length of stay. Based on these data, Australian treatment guidelines now recommend repeat testing for 2 h paracetamol serum concentrations >100 mg/L (0.67 mmol/L). Conclusion: A paracetamol serum concentration between 2 h and 4 h post-ingestion in children <6 years-old with unintentional poisonings of paracetamol liquid can facilitate medical discharge.

Abstract Introduction Coronavirus disease COVID-19 rapid antigen tests are a useful tool in detecting infection, and their use has increased in many countries since they became commercially available in late 2021. Some rapid antigen tests contain sodium azide, which can be toxic in small doses. This study aimed to describe the clinical characteristics of exposures to COVID-19 rapid antigen tests. Methods This is a prospective study conducted by the New South Wales Poisons Information Centre. From 22 January 2022 to 31 August 2022, rapid antigen test exposures were followed up to obtain outcome information. Data collected included: brand/ingredients, exposure route, demographics, symptoms, and disposition. Results We recorded 218 exposures in the seven-month study period. Complete follow-up information was available in 75% (n = 164). There were 53 exposures to sodium azide-containing products (35 with follow-up data) and 165 to non-sodium azide-containing products and unknown ingredient exposures (129 with follow-up data). Overall, unintentional exposures predominated (n = 182), and 151 were ingestions. The vast majority (>90%) did not develop symptoms, and all symptoms that developed were mild. Most cases (95%, n = 208) did not require referral to a healthcare facility. Conclusions In this prospective series, few patients developed symptoms, regardless of the sodium azide content, likely due to low concentration and low volume within the test kits. However, ongoing toxicovigilance is warranted.