An Audit of Paediatric Prescribing of Amoxicillin

Sir

Oral penicillin, predominantly amoxicillin, is the most commonly prescribed antibiotic for children worldwide¹. In recent years antibiotic prescribing has been repeatedly audited as antibiotic resistance remains a community and global threat1,2

Paediatric dosing in Ireland follows the dosing recommendations in the SARI guidelines (www.antibioticprescribing.ie)3 or the British National Formulary for Children (BNFC)4. The guidance on the correct dose is often confusing giving the prescriber the option of dose per weight or per age-bands. These age bands are classified as 1-12months, 1-5 years, and 5-12 years4. Oral prescribing guidelines for amoxicillin were updated in the BNFC in 2014, for the first time since their introduction in 1963. This was mainly to address concerns that children may have been receiving inadequate doses, along with the escalation of antibiotic resistance and an increase in the average paediatric weight. The net result was an increase in the dose of amoxicillin prescribed for each clinical indication. In response to the updated guidelines we audited the prescribing practice of amoxicillin in children.

The audit was carried out in three GP training practices in the Mid-Western area of Ireland from 31st August 2014 to September 1st 2015. Nine prescribers were identified in the three practices consisting of six GPs and three GP registrars. An estimated total population served by these practices is 10,200 patients. All prescriptions of amoxicillin issued to children from age 1 month to 12 years inclusive were analysed. These prescriptions were categorized into age groups of; less than 12 months, 1-5years and 5-12 years in keeping with recommended age-bands in the BNFC. Data analysis was carried out using Excel 2007 (Microsoft Corporation Inc). In total, 336 patients were identified of which 7 were excluded as no antibiotic dose was recorded. Three hundred and twenty-nine patients were included in the final analysis. The dose of amoxicillin prescribed was incorrect in 84.2% of cases as per the BNFC age-band guidelines. In the 5-12 years age-band 97.7% (128/131) of the doses given were incorrect. All doses given were subtherapeutic. In the 1-5 year age-band 89% (147/165) of the doses given were incorrect. All doses again were sub therapeutic. However, in the under 12 months category, 94% (31/33) of prescriptions were given at the correct dose. Dose per weight is an alternative method of antibiotic dose calculation. However, 93% of cases had no weight recorded therefore this method of dose calculation would have been impossible in the majority of cases. This study highlighted that amoxicillin is being prescribed in sub therapeutic doses for children in 84% of cases.

This audit highlighted that GPs haven’t fully adjusted to new paediatric prescribing guidelines. As a result, we recommend further education in paediatric prescribing. For precise prescribing in children, a weight based approach is most accurate. However if this is not practical, the updated age-band dosing as per BNFC 2014 is a reliable alternative1. The areas of age-band prescribing causing concern would be children at the upper and lower limits of each age-band and children during the phases of rapid growth3.

Dr Siobhan Twohig, Dr Harrold’s Medical Practice, Tyone, Nenagh, Co Tipperary
Email: siobhantwohig@gmail.com

References 

  1. Saxena S, Ismael Z, Murry M, et al. Oral Pencillin Prescribing for Children in the UK: a Comparison with BNF for Children Age-Band Recommendations. Br J Gen Pract 2014 April;64:217-222.
  2. Laxminarayan R, Duse A, Wattal C, et al. Antibiotic resistance: the need for global solutions. Lancet Infect Dis 2013; 13: 1057–1098.
  3. Guidelines for Antimicrobial Prescribing In Primary Care In Ireland [Internet]. Ireland: The Community Antimicrobial Stewardship subcommittee of the SARI National Committee;2014/2015. Accessed 2015 Sept 2. Available from : http://www.antibioticprescribing.ie
  4. BNF for Children.2014/2015. London. BMJ Group. 2014/2015.

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