Penicillin prescriptions risk under-dosing children, experts say

March 25, 2014, King's College London

Millions of children in the UK are potentially receiving penicillin prescriptions below the recommended dose for common infections, according to new research led jointly by researchers at King's College London, St George's, University of London and Imperial College London. The authors are calling for an urgent review of penicillin dosing guidelines for children - which at the time of study had not changed in over 50 years - after discovering wide variation in current prescribing practice.

The research adds to growing concern about the global threat of antibiotic resistance, whereby misuse of antibiotics leads to the emergence of bacteria that cannot be controlled by available medicines.

Published today in the British Journal of General Practice, the study is the first to examine actual prescriptions of oral penicillins, the most commonly prescribed antibiotics for children worldwide, by GPs in the UK.

Analysing data from the IMS Disease-Analyzer database, researchers found that of the children under the age of one who were prescribed amoxicillin - the most commonly prescribed oral - none of them were prescribed the dose recommended (62.5 mg per unit) by the British National Formulary for Children (BNFC). In fact, the majority received double the recommended dose (125 mg).

96 percent of children aged 1-5 received the recommended dose but 40 per cent of 6-12 year olds and 70 per cent of 12-18 year olds were prescribed unit-doses below the BNFC guidelines. Similar patterns of prescribing were found for penicillin V and flucloxacillin.

The study, funded by the National Institute for Health Research (NIHR) Biomedical Research Centre at Guy's and St Thomas' NHS Foundation Trust and King's College London, also looked specifically at prescriptions for ear infection, the most common condition in childhood that can lead to the prescription of oral penicillin, and found that children under the age of one were the only group who received the recommended dose of amoxicillin. For children aged 4-15 years the prescriptions equated to approximately 33 per cent of the recommended dose.

Millions of children in the UK are potentially receiving penicillin prescriptions below the recommended dose for common infections, according to new research led jointly by researchers at King's College London, St George's, University of London and Imperial College London. The authors -- including Dr Paul Long of King's and Dr Sonia Saxena of Imperial College London -- are calling for an urgent review of penicillin dosing guidelines for children. Credit: King's College London.

Dosing guidelines for oral penicillin are currently provided by the BNFC and are determined by age and weight-bands. Although guidelines specifically for amoxicillin did change late last year, the authors suggest this has only made the situation worse, particularly in the approval of a new, wider 5-18 age band.

Dr Paul Long, Reader in Pharmacognosy at King's College London, said: '12-18 year olds should have received a 500mg dose based on pre-2013 guidance but our study shows that many of these teenagers were actually prescribed 250mg. Introducing a new 5-18 age band would seemingly justify a 250mg prescribing practice, but actually only further exacerbates potential under-dosing in the 12-18 age group.'

Another problem with the current guidelines, according to the researchers, is that they do not take into account how the average weight of children has changed over time. Due to the rising prevalence of childhood obesity, prescriptions based on age-bands could lead to doses prescribed at too low a level to produce a therapeutic effect (sub-therapeutic dosing).

This new study follows a literature review of evidence in 2011 to understand the origins of dosing guidelines, which found that prescribing based on age-bands had first been suggested in the early 1950s. Following these findings, a general recommendation to use age banding for all antibiotics in children was published in the BMJ in 1963, and these same recommendations remain in use today. This is despite the re-evaluation of guidelines for adult penicillin prescriptions, which did take modern weights into consideration.

The authors attribute wide variation in prescription practice to the complicated nature of current guidelines. Dr Long of King's College London said: '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. Age and weight bands are well established but there is no standardised or evidence-based guideline to clarify which method of dose selection is best.

'The need to review these is more urgent than ever as it is clear from ourresearch that age-banding doses is no longer appropriate.

'A detailed qualitative assessment of prescriber practice is also required to understand reasons for the use of age-bands and the barriers to implementation of weight-based dosing.'

Dr Sonia Saxena, co-author from the School of Public Health, Imperial College London and a practising GP, said: 'It is important now to understand why GPs are prescribing sub-therapeutic levels of penicillin. Some GPs may be erring on the side of caution, prescribing low doses to avoid errors or side effects.'

Dr Saxena added: 'In the majority of cases children will still get better, but undertreating those who do need antibiotics could mean more infectious complications and more health contacts overall.'

Explore further: Penicillin doses for children should be reviewed, say UK experts

Related Stories

Penicillin doses for children should be reviewed, say UK experts

December 16, 2011
A team of scientists and clinicians, led by researchers at King's College London and St George's, University of London, are calling for a review of penicillin dosing guidelines for children, as the current guidelines have ...

Scottish data highlight dangerous practice in pediatric paracetamol prescribing

May 19, 2011
Many of the prescriptions issued by GPs for paracetamol either give less than recommended doses to older children or exceed recommended doses in young children. Under-dosing may result in insufficient pain relief and over-dosing ...

Carers and pharmacists confused about paracetamol doses for overweight kids

August 20, 2012
The correct therapeutic dose is important for this commonly used painkiller, say the authors, because it is potentially fatal to give too high a dose; and too low a dose may result in more serious illness.

Most pediatric procedural pain guidelines of average quality

February 3, 2014
(HealthDay)—Most clinical practice guidelines for procedural pain in children are of average quality and most do not provide tools to help clinicians apply the recommendations in practice settings, according to research ...

Decline of antibiotic use among kids seems to be leveling off

February 4, 2014
(HealthDay)—A downward trend in antibiotic use among children may have leveled off in certain areas of the United States, a new study shows.

AAP approves childhood immunization schedules for 2014

January 31, 2014
(HealthDay)—The recommended childhood and adolescent immunization schedules for 2014 have been approved, according to an American Academy of Pediatrics (AAP) policy statement published in the Feb. 1 issue of Pediatrics.

Recommended for you

In most surgery patients, length of opioid prescription, number of refills spell highest risk for misuse

January 17, 2018
The possible link between physicians' opioid prescription patterns and subsequent abuse has occupied the attention of a nation in the throes of an opioid crisis looking for ways to stem what experts have dubbed an epidemic. ...

Patients receive most opioids at the doctor's office, not the ER

January 16, 2018
Around the country, state legislatures and hospitals have tightened emergency room prescribing guidelines for opioids to curb the addiction epidemic, but a new USC study shows that approach diverts attention from the main ...

FDA bans use of opioid-containing cough meds by kids

January 12, 2018
(HealthDay)—Trying to put a dent in the ongoing opioid addiction crisis, the U.S. Food and Drug Administration on Thursday slapped strict new restrictions on the use of opioid-containing cold and cough products by kids.

Taking ibuprofen for long periods found to alter human testicular physiology

January 9, 2018
A team of researchers from Denmark and France has found that taking regular doses of the pain reliever ibuprofen over a long period of time can lead to a disorder in men called compensated hypogonadism. In their paper published ...

Nearly one-third of Canadians have used opioids: study

January 9, 2018
Nearly one in three Canadians (29 percent) have used "some form of opioids" in the past five years, according to data released Tuesday as widespread fentanyl overdoses continue to kill.

Growing opioid epidemic forcing more children into foster care

January 8, 2018
The opioid epidemic has become so severe it's considered a national public health emergency. Addiction to prescription painkillers, such as oxycodone and morphine, has contributed to a dramatic rise in overdose deaths and ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.