Use of antipsychotic drugs among Dutch youths between 1997 and 2005

The authors examined prevalence, incidence, and duration of antipsychotic drug use in the northern and eastern regions of the Netherlands between 1997 and 2005 among youths in regard to age, gender, and class of drug.

Prescription drug dispensing data were collected from community pharmacies in the northern Netherlands (www.iadb.nl). Prevalence, incidence, and duration of use were studied among roughly 100,000 youths ranging in age from infancy to age 19 years, calculated by age group (zero to four years, five to nine years, ten to 14 years, and 15 to 19 years), for boys and girls, and for first- and second-generation antipsychotics. Duration of use was compared between youths who started antipsychotic treatment in 1998-1999 and those who started in 2001-2002.

From 1997 to 2005, prevalence increased from 3.0 to 6.8 per thousand. Prevalence was highest among ten-year-olds to 14-year-olds (11 per thousand), especially among boys (17 per thousand). The increased prevalence was mainly attributable to an increased use of second-generation antipsychotics and to a longer duration of use. Median duration of use doubled from .8 year in 1998-1999 to 1.6 years in 2001-2002.

Second-generation antipsychotic drugs were increasingly prescribed, and for longer periods of time, to younger children, probably because of new indications. This practice increases the exposure of a young population to (partly unknown) risks.