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

4. Introduction
Psychotropic medicines have been available for physicians to prescribe since the middle of the
1800s. Although the active ingredients have changed over time, most of them have been associated
with dependence (1,2). Barbiturates were introduced into the market in 1903 for treatment of
insomnia and anxiety, but because of the risk of intoxication, dependence and misuse, the
barbiturates were slowly replaced by the benzodiazepines, which have been available since the late
1950s (1,2). At the peak of their use, about 10% of the Danish population could have taken them on
a daily basis (1), and they are still widely used, although the risk of dependence has been known
since the beginning of the 1960s (1,3,4).
Before the 1950s, the general perception was that the transmission between the nerves was based on
electric signals. During the 1950s and 1960s it became accepted that this transmission process was
chemical and that it involved neurotransmitters like dopamine, norepinephrine, acetylcholine and
serotonin. Modern psychotropic drugs developed from 1950 and onwards were believed to have
more specific effects on the patient´s mood, thoughts and behaviour. This was the beginning of
intensive research into molecular structures, receptors and the relation to specific disorders, which
established connections between psychiatric aetiology, psychopharmacology and development and
marketing of new psychiatric drugs (5).
In 1988, the so-called selective serotonin reuptake inhibitors (SSRIs) were introduced as new
antidepressants and expectations were very high regarding efficacy and safety (2,4). The use of
SSRIs rapidly increased in many countries and continued to increase during the next approximately
30 years without any peak or indication of a decrease (6).
Several studies have described increasing use of SSRIs and a decreasing use of benzodiazepines. A
few studies have looked at overall usage (1,2) but most have focused on specific therapeutic drug
groups (1,3,4,). Some international studies have described usage trends for antidepressants, all
showing an increase from the beginning of the 1990s, due to the SSRIs, although in Australia, the
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