This article is more than 5 years old. Information may no longer be current.
Penicillin prescriptions often risk underdosing children
Click Here to Manage Email Alerts
Penicillin prescriptions less than the recommended dose for common infections are often given to children in the United Kingdom, according to recent study findings published in the British Journal of General Practice.
“Although oral penicillins have been widely used for over 50 years to treat infections in children, the dosing guidelines have remained complicated, which carries the risk of confusing prescribers,” Paul Long, PhD, of King’s College London, said in a press release. “Age and weight bands are well established, but there is no standardized or evidence-based guideline to clarify which method of dose selection is best. The need to review these guidelines is more urgent than ever as it is clear from our research that age-banding doses is no longer appropriate.”
Long and colleagues evaluated 388,926 children aged 0 to 18 years to determine actual oral penicillin prescribing by general practitioners among those age groups. Overall, there were 65,737 oral penicillin prescriptions written including: amoxicillin (63%), penicillin V (17%) and flucloxacillin (20%). Flucloxacillin is not approved for use in the United States.
For amoxicillin, no patients younger than 1 year received the recommended dose; most of those patients received double. In contrast, 96% of patients aged 1 to 5 years received the recommended dose. However, doses less than the British National Formulary for Children were prescribed for 40% of patients aged 6 to 12 years and 70% of patients aged 12 to 18 years.
Similar results were found for prescriptions for penicillin V and flucloxacillin. No patients in the group of patients younger than 1 year received the recommended doses compared with patients aged 1 to 5 years who received the proper medication dosages. Patients younger than 9 years were more often prescribed the dose recommended for patients aged 1 to 5 years; however, patients aged 9 to 12 years were more likely to receive the recommended dose.
“It is important now to understand why [general practitioners] are prescribing sub-therapeutic levels of penicillin,” Sonia Saxena, MD, of the School of Public Health, Imperial College London, said in the release. “Some [general practitioners] may be erring on the side of caution, prescribing low doses to avoid errors or side effects. In the majority of cases, children will still get better, but undertreating those children who do need antibiotics could mean more infectious complications and more health contacts overall.”
Paul Long, PhD, can be reached at Institute of Pharmaceutical Science, King's College London, 150 Stamford Street, London SE1 9NH, United Kingdom; email: paul.long@kcl.ac.uk.
Disclosure: Some of the researchers report specific relationships with Wyeth Vaccines of John Wyeth & Brother Ltd. or with Pfizer UK. See the study for a full list of disclosures.
Perspective
Back to Top
Edward A. Bell, PharmD, BCPS
This study was conducted in the United Kingdom, and, in part, may not be applicable to antibiotic prescribing habits in the United States. Antimicrobial resistance patterns and the availability of specific antibiotic products (such as flucloxacillin, which is not available in the United States) are examples. However, other aspects of this study may be applicable to US clinicians, and important to consider. An appropriate dose of an antimicrobial agent depends upon several factors: indication and severity, patient age, patient weight, patient organ function, antimicrobial resistance patterns, and concomitant drug therapy (eg, drug-drug interactions), among other factors. In pediatrics, some of these factors assume increased relevance. We know that the pharmacokinetics (ie, the most appropriate dose and dosing schedule) of some drugs vary considerably in pediatrics by patient age. While many advancements have been made in the past few decades in this area, much is still yet to be learned. Some drugs are commonly dosed by age range in the United States as well. While this dosing method is easy and may suffice for many uses, it is likely not as accurate as patient-specific weight-based dosing (which takes a few more steps to determine). These authors’ conclusions are applicable here as well – a focus on the dynamics of accurate drug prescribing for antimicrobials, including research on pediatric pharmacokinetics, and antimicrobial resistance patterns, among others, should be a never-ending process.
Click Here to Manage Email Alerts