Psychotropic drug use in the Norwegian general population in 2005: data from the Norwegian Prescription Database

To analyse psychotropic drug utilisation patterns in the general population of Norway in 2005.

Data on 4,163,045 prescriptions of psychotropic drugs dispensed at all pharmacies in Norway during 2005 were extracted from The Norwegian Prescription Database (NorPD), including antipsychotics (ATC-code N05A), anxiolytics (N05B), hypnotics (N05C) and antidepressants (N06A). This information was merged with data concerning the 3857 general practitioners (GPs) from the Norwegian Regular GP Scheme.

A total of 705,230 individuals, or 15.3% of the general population, received at least one prescription of a psychotropic drug. The figures for the four therapeutic subgroups were 2.4% for antipsychotics, 6.2% for anxiolytics, 7.9% for hypnotics and 6.0% for antidepressants, respectively. For all subgroups, prevalence was higher among women than among men, and increased steadily by patients' age. The mean annual drug volume per patient was highest among persons aged 40-59 years, except for hypnotics where it continued to increase with age. GPs prescribed 80% of overall psychotropic drug volume, psychiatrists 5%, and other prescribers 15%. The proportion of the drugs issued by the three prescriber groups differed with the patients' age group. While children and adolescents received a relatively large share from paediatricians and child and adolescent psychiatrists, adults mostly got their prescriptions from GPs.

The majority of psychotropic drugs were prescribed by GPs. Overall drug use increased significantly, and psychiatrists' contribution decreased significantly with patients' age. The quality of pharmacological treatment for mental health problems of the general and aging population therefore relies mainly on the GPs.