Risk factors for unlicensed and off-label drug use in children outside the hospital.

OBJECTIVE: To establish risk factors of unlicensed and off-label drug use by children outside the hospital.

METHODS: A cross-sectional study based on 66 222 pharmacy dispensing records for the year 2000 was performed in the northern part of the Netherlands. All prescriptions were divided into the following categories: unlicensed (no product license), off-label (licensed drugs used outside the terms of the product license), and on-label (licensed drugs used according to the product license). For identifying possible problem areas, the proportions of unlicensed and off-label drug use were determined per age group (0-1, 2-5, 6-11, or 12-16 years) and per drug group. For all systemic drugs, a logistic regression was done that models the odds of receiving an unlicensed or off-label prescription as a function of several possible risk factors.

RESULTS: Unlicensed drug use in Dutch children is the highest among 0 to 1-year-olds, and off-label drug use is the highest among 12- to 16-year-olds. Drug groups with highest percentages of unlicensed and off-label drug use were ophthalmologicals/otologicals (80.7% of all prescriptions in this group), blood and blood-forming organs (mainly vitamin K for breastfed newborns; 75.7%), cardiovascular drugs (74.7%), and dermatologicals (73.3%). Prescriptions by specialists (outpatient), prescriptions for new drugs, prescriptions for drugs with a low use in the pediatric population, and prescriptions for infants were risk factors for using a systemic drug unlicensed or off-label.

CONCLUSION: Efforts to improve pediatric labeling are important and need full support. The present results can be used to focus these efforts.