Presentations Related to Acute Paracetamol Intoxication in an Urban Emergency Department in Switzerland

Aim. To investigate the characteristics of Emergency Department (ED) presentations due to acute paracetamol intoxication. Methods. Retrospective observational study of patients presenting to the ED of Bern University Hospital between May 1, 2012, and October 31, 2018, due to a paracetamol overdose (defined as intake of >4 g/24 h). Cases were identified using the full-text search of the electronic patient database and were grouped into intentional (suicidal/parasuicidal) and unintentional intoxications (e.g., patient unaware of maximal daily dose). Results. During the study period, 181 cases were included and 143 (79%) of those were intentional. Compared to the patients in the unintentional group, patients in the intentional group were more often female (85% vs 45%, p<0.001) and younger (median age 23.0 vs 43.5 years, p<0.001), more frequently suffered from psychiatric comorbidities (93%, (including 49% with borderline personality disorder) vs 24%, p<0.001), and paracetamol was more often taken as a single dose (80% vs 13%, p<0.001). Although the median daily ingested dose was lower in the unintentional than in the intentional group (8.2 g vs 12.9 g, p<0.001), patients in the unintentional group presented later (29% vs 84% within 24 h of ingestion, p<0.001), included more cases of acute liver failure (nine (24%) vs six (4%), p<0.001), and were more often hospitalised (24% vs 52% treated as outpatients, p=0.002). There were no significant differences between the groups regarding drug-induced liver injury (seven cases (5%) in the intentional and one (3%) in the unintentional group) or fatalities (one in each group). Conclusions. The majority of presentations due to paracetamol poisoning were intentional, most commonly in female patients with borderline personality disorder. Patients with unintentional paracetamol intoxication had worse outcomes with respect to acute liver failure and hospitalisation. Future preventive measures should raise awareness of paracetamol toxicity in the general population and encourage particular attention and frequent follow-ups when prescribing paracetamol for vulnerable groups.