BACKGROUND: Prescribing of selective serotonin reuptake inhibitors (SSRIs) has increased dramatically. OBJECTIVE: To compare the sales of benzodiazepines and SSRIs within the primary care sector in Denmark and relate changes in usage to number of indications and products on the market. METHODS: We used data from various sources to establish the sales curves of psychotropic drugs in the period 1970 to 2007, based on the Anatomic Therapeutic Classification system and Defined Daily Doses. RESULTS: Fluctuations in sales of psychotropic drugs that cannot be explained by disease prevalence were caused by changes in sales of the benzodiazepines and SSRIs. We found a decline in the sales of benzodiazepines after a peak in 1986, likely due to the recognition that they cause dependence. From a low level in 1992, we found that the sales of SSRIs increased almost linearly by a factor of 18, up to 44 DDD per 1000 inhabitants, which was closely related to the number of products on the market that increased by a factor of 16. CONCLUSIONS: Sales of antidepressant drugs are mainly determined by market availability of products indicating that marketing pressures are playing an important role. Thus the current level of use of SSRIs may not be evidence-based, which is supported by studies showing that the effect of SSRIs has been overestimated.
BACKGROUND: Prescribing of selective serotonin reuptake inhibitors (SSRIs) has increased dramatically. OBJECTIVE: To compare the sales of benzodiazepines and SSRIs within the primary care sector in Denmark and relate changes in usage to number of indications and products on the market. METHODS: We used data from various sources to establish the sales curves of psychotropic drugs in the period 1970 to 2007, based on the Anatomic Therapeutic Classification system and Defined Daily Doses. RESULTS: Fluctuations in sales of psychotropic drugs that cannot be explained by disease prevalence were caused by changes in sales of the benzodiazepines and SSRIs. We found a decline in the sales of benzodiazepines after a peak in 1986, likely due to the recognition that they cause dependence. From a low level in 1992, we found that the sales of SSRIs increased almost linearly by a factor of 18, up to 44 DDD per 1000 inhabitants, which was closely related to the number of products on the market that increased by a factor of 16. CONCLUSIONS: Sales of antidepressant drugs are mainly determined by market availability of products indicating that marketing pressures are playing an important role. Thus the current level of use of SSRIs may not be evidence-based, which is supported by studies showing that the effect of SSRIs has been overestimated.