Objectives To determine what dose of paracetamol a group of carers and pharmacists would administer to an overweight or obese child, and to observe the paracetamol doses administered to children that presented to the emergency department of a paediatric tertiary referral hospital.

Methods This study was composed of two stages: a survey of carers (recruited from community pharmacies) and community pharmacists and an observational study of the paracetamol dosing practices at the emergency department of a paediatric tertiary referral hospital.

Results While carers (n = 45) and pharmacists (n = 28) recommended similar paracetamol doses for children who were the normal weight for their age, as body weight increased, there was an increasing array of responses. The doses administered to the 86 children that presented to the emergency department of a paediatric tertiary referral hospital were based upon total body weight. As body mass index increased, the dosage administered was likely to be higher when the dose was adjusted for the ideal body weight (IBW), and two out of three obese children were administered a dose over 20 mg/kg of IBW.

Conclusions There is substantial confusion amongst carers and pharmacists regarding the most appropriate dose of paracetamol that should be administered to overweight and obese children. In the emergency department setting, overweight and obese children did not have any empirical dose reduction according to the amount they were above IBW—whether or not this is appropriate practice is unclear, but it does highlight the need to develop simple, evidence-based guidelines for dosing these children.