1 Selective serotonin reuptake inhibitors (SSRI) – sales, withdrawal ...

The data in the register represent sales and prescribing data but they cannot be taken as equivalent
to taken drugs. Some of the prescribed and sold drugs will never be taken as prescribed and there is
little knowledge about what happens to the drugs after purchase in a pharmacy. All purchases of
prescribed drugs in a pharmacy are included in the register. There might be a minor proportion of
drugs offered in outpatient clinics or by general practitioners, as free samples are given by drug
companies, resulting in under-reporting. Given these considerations, there is no reason to assume
that the Register of Medicinal Product Statistics should not be valid.
Data about products and indications were obtained from the Danish Drug Index, which has been
published yearly in the whole period. Danish Drug Information, owned by The Danish Association
of the Pharmaceutical Industry, has published the Danish Drug Index.
We performed a correlation coefficient analysis of the association between DDD sales numbers and
number of products well knowing that it is not possible to conclude about causation. Thus the study
can make it plausible that there is an association between the sales and marketing.
We looked at all psychotropic drugs and the changes in sales pattern. This could be discussed,
because they are very different drugs, e.g. antidementia drugs, antidepressants and hypnotics. This
gave though an overview of the changes in sales patterns including treatment changes between
drugs, e.g. between benzodiazepines and SSRIs, which together represented the main part of the
sales of psychotropic drugs.
By means of a combination of three data sets of the sales of psychotropic drugs it was possible to
construct sales curve of psychotropic drugs in Denmark in the primary health care sector over a 37
years period.
Results
The sales of psychotropic drugs have fluctuated considerably over time even though the prevalence
of the diseases should be expected to be about the same (figure 1). When the total sales of
psychotropics were split into drug groups, sales of group N05, which contains the benzodiazepines,
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