Doses of penicillin given to sick children should be reviewed, experts from King's College London and St George's, University of London have claimed.

Current guidelines have been in place for 50 years, but the experts claim they should be looked at as children are getting heavier, meaning they might not be getting the correct dose of medicine.  The guidelines suggest that a baby aged up to one weighs 10kg, a two-year old weighs 13kg, a five-year old 18kg and a 10-year old 30kg.

However, the Health Survey for England 2009 found that the average weight of a five year old is now 21kg and a 10-year old is 37kg.

Dr Paul Long, who was involved in the research, said: "We were surprised at the lack of evidence to support the current oral penicillins dosing recommendations for children, as it is such a commonly used drug.

"Children's average size and weight are slowly but significantly changing, so what may have been adequate doses of penicillin 50 years ago are potentially not enough today."

In the intervening 50 years since the guidelines were first issued, adult dosages of penicillin have been reviewed twice.

The Medicines and Healthcare Products Regulatory Agency recently called for children's paracetamol dosages to be reviewed.

Posted by Robert Mair on 16/12/2011