A male doctor wearing a white coat injects medication into the arm of a young boy.

Weight-based medication errors in children

HSIB legacy content

HSIB legacy content

This investigation was carried out by the Healthcare Safety Investigation Branch (HSIB). Find out more about HSIB legacy.

National investigation

Studies show that prescribing errors are the most frequent type of medication error in children’s inpatient settings.

This investigation looks at the risks involved when prescribing, dispensing and administering medicine to children.

Prescribing for children is usually personalised: individual calculations are needed for each child, taking weight, age, gestation and body surface area into account.

Electronic prescribing and medicines administration (ePMA) systems are now frequently used in children’s services. They are considered a more effective way to reduce medication errors however, they may cause new technology-related errors.

Errors in prescribing for children can lead to unsafe doses of medicines, causing significant harm or death if administered.

Reference event

The investigation was launched after we were notified of an event involving a four-year-old child.

The child was diagnosed with a blood clot in her leg following a surgical procedure in hospital. A multidisciplinary team (MDT) agreed a plan, which was for the child to be prescribed an anticoagulant medicine, calculated as units per kilogram, twice a day.

The medicine was prescribed by a junior doctor using an ePMA system, which had been implemented on the children’s ward 10 months before the incident.

Errors in the prescription, dispensing and administration processes meant that the child received 10 times the intended dose on five separate occasions over three days.

A scan of the child’s brain showed evidence of a bleed and she was admitted to the paediatric intensive care unit. Following three months in hospital, the child was discharged home with an ongoing care plan.

Investigation summary

This investigation:

  • Draws on the field of human factors to explore the elements that both support and inhibit multidisciplinary teamworking.
  • Examines the factors which contribute to a reduction in the effectiveness of checking as a barrier to medication errors.
  • Seeks to identify the risks associated with the implementation of ePMA systems in clinical areas using weight-based paediatric prescribing and administration.
Investigation report