Reasons for antidepressant prescriptions in Canada.

Purpose: To describe reasons reported by physicians making recommendations for treatment with antidepressant medications.

Methods: Data collected by IMS Health Canada in a database called the Canadian Disease and Therapeutic Index (CDTI) were used in this analysis. CDTI data are collected from a representative sample of office-based physicians who complete diaries in their practices during selected sampling periods. A drug recommendation is recorded each time a treatment is recommended. The data are weighted to produce national estimates of the frequency of such recommendations.

Results: The frequency of recommendations for antidepressant treatment increased between 2000 and 2004. However, there was a slight decrease in 2005. Two types of antidepressant medications, tricyclic antidepressants (TCAs) and trazodone showed distinct patterns of use. TCAs were more commonly used for non-psychiatric indications than for psychiatric indications, especially for sleep- and pain-related reasons. Trazodone was frequently recommended for sleep problems. The proportion of recommendations for depressive disorders for antidepressants as a group remained stable over the 5-year study period.

Conclusions: About one-third of antidepressant recommendations are for reasons other than depression. It can no longer be assumed that the frequency of antidepressant use is a measure of the frequency of pharmacological depression treatment. However, prescription data may be useful for tracking trends.