Unlicensed and off label drug use by children in the community: cross sectional study

Participants, methods, and results

In the Netherlands people commonly register with one pharmacy, from which they obtain their drugs, including those prescribed as outpatients. Excluded are drugs used during hospital stays and those bought over the counter. We obtained our data on dispensing from the InterAction database, which covers part of the northern Netherlands.

We selected all prescriptions for children aged 0-16 years in 2000. Dutch pharmacies are allowed to prepare their own formulations and to modify commercial preparations. These pharmacy based preparations are exempt from licensing, and we classified them as unlicensed. For each prescription of a licensed drug (all remaining prescriptions) we examined the official licence information—the summary of product characteristics—in detail. We determined whether the summary mentioned use in children and, if so, the minimum age. When age was unspecified we set it at a minimum of 0 years. If use in children was not mentioned or was advised against without an indication of age, we set the minimum age at 18 years. We considered that a drug with a product licence was used according to the label if the summary of product characteristics stated that it could be used in children, and if the child was of the minimum age for use or older; otherwise we considered the drug was used off label. As information about indications was not available, we were not able to distinguish between different indications in the summary.

We analysed 68 019 prescriptions for 19 283 children aged 0-16 years. General practitioners were responsible for 56 961 (83.7%) of the prescriptions; the remainder came from specialists. Unlicensed drugs amounted to 16.6% (11 288) of the total prescriptions and were mainly dermatological and liquid preparations.

The table shows the official labelling of drugs prescribed for children. In 21.3% of the prescriptions for licensed drugs, use in children was not mentioned in the summary, and 19.7% mentioned use in children but without any indication of age. Although the summaries of remaining drugs indicated age, children were often divided into just two age groups.

Overall, 22.7% (15 453) of the prescriptions for children were used off label. Drug groups with the highest percentages of off label use were urologicals or sex hormones (mainly oral contraceptives; 85.9%), ophthalmological and otological drugs (79.4%), dermatological drugs (55.9%), and cardiovascular drugs (48.3%). In the group with the highest number of prescriptions—respiratory drugs—16.1% of all prescriptions were used off label.

Comment

Many licensed drugs used by children in the community are poorly labelled for use in children, resulting in high percentages of off label use. Therefore labelling for children needs to be improved, with the support of everyone working in pharmacotherapy.