Objectives: To measure the dose discrepancy in prescribing simple paediatric analgesia, in the emergency department, by comparing age and actual weight-based dosing. To establish the accuracy of the weight-estimation formula for children [weight kg=2 (age years+4)].
Methods: A prospective survey conducted in the emergency departments of a UK teaching hospital and district general hospital. Two hundred and forty-seven children were prescribed simple analgesia in the form of paracetamol and ibuprofen or both. The dose prescribed was based on age. All children were weighed and a maximum dose based on the child's weight was calculated. The individual child's weight was also compared with the weight calculated using the estimation formula.
Results: A total of 247 patients were included. Two hundred and thirty-three patients were prescribed paracetamol. Fifteen patients were prescribed ibuprofen. The paracetamol group was administered a mean dose that was 67% (P<0.001) of the optimal dose that was based on weight. Ibuprofen dosage was 51% (P<0.001) of optimal dose. The weight-estimation formula underestimated weight by 16% (P<0.001).
Conclusions: Prescribing analgesia by age often results in significant underdosing in the paediatric population. Predicting a child's weight using the calculation may result in underdosing.