title: Overdose with modified-release paracetamol (Panadol Osteo®) presenting to a metropolitan emergency medicine network: a case series.
abstract: BACKGROUND
  There are currently no large cases series documenting poisoning with paracetamol modified-release (Panadol Osteo®, GlaxoSmithKline, Sydney, NSW, Australia). Management guidelines recommend at least two serum paracetamol concentrations 4 h apart and initiating treatment with N-acetylcysteine (NAC) if more than 10 g is ingested.
  
  
  OBJECTIVE
  To describe a cohort of Panadol Osteo® poisoning and determine if the management of identified cases was consistent with existing guidelines.
  
  
  METHODS
  Descriptive retrospective case series presenting to a metropolitan hospital network with paracetamol poisoning from October 2009 to September 2013.
  
  
  RESULTS
  There were 42 cases of Panadol Osteo® poisoning identified. Twenty-nine patients (median ingested dose 19 950 mg) were treated with NAC, of which 27 were acute single ingestions. Of NAC-treated patients, 85% (23/27) had an initial serum paracetamol concentration that was above the nomogram line. However, 15% (4/27) had an initial non-toxic concentration that later increased above the line. In 14 untreated patients (median ingested dose 7980 mg), one was an unrecognised late line-crosser with initial non-toxic serum paracetamol concentration. Only 43% (6/14) had a repeat paracetamol concentration measured. Three patients had a 4 h paracetamol >500 μmol/L. Late line-crossing was seen in the NAC-treated group at this level. In two untreated patients, NAC should have been commenced on the reported dose.
  
  
  CONCLUSIONS
  Most patients presenting with Panadol Osteo® poisoning requiring NAC treatment had an initial serum paracetamol concentration indicating need for treatment. A small number of late treatment nomogram line-crossers was seen on repeat paracetamol estimation. The current guideline for Panadol Osteo® poisoning would have detected all cases requiring NAC treatment.
authors.affiliation: Monash Emergency Medicine Program and Clinical Toxicology-Addiction Medicine Service, Monash Health, Melbourne, Victoria, Australia; School of Clinical Sciences at Monash Health, Monash University, Melbourne, Victoria, Australia.
authors.forename: Andis
authors.initials: A
authors.lastname: Graudins
mesh_terms: D000082:Acetaminophen / Q000097:blood / Q000506:poisoning*; D000111:Acetylcysteine / Q000627:therapeutic use*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D054869:Clinical Audit; D003695:Delivery of Health Care / Q000592:standards*; D062787:Drug Overdose / Q000175:diagnosis / Q000209:etiology / Q000628:therapy*; D004632:Emergency Medical Services; D005260:Female; D019983:Guideline Adherence / Q000592:standards; D006801:Humans; D008297:Male; D008875:Middle Aged; D017410:Practice Guidelines as Topic; D012189:Retrospective Studies; D013997:Time Factors; D055815:Young Adult
chemical_list: D000082:Acetaminophen; D000111:Acetylcysteine
keywords: N-acetylcysteine; modified-release; overdose; paracetamol; poisoning