Why were the sexual side effects of selective serotonin reuptake inhibitors (SSRIs) initially overlooked?
The initial clinical focus was on the improved tolerability and safety of SSRIs compared to tricyclic antidepressants (TCAs). The TCAs first appeared approximately 20 years ago, followed by fluoxetine entering the market in 1998. Their side effects included constipation, blurred vision, urinary retention, and cardiac effects. In addition, newer agents appeared to be safer than TCAs, particularly with respect to overdose risk. Since a systemic study of adverse events was not conducted and published at that time, the prevalence rate of sexual dysfunction was determined by spontaneous reports in registration trials. These reports dramatically underestimate the occurrence rates of sexual dysfunction. In addition, depression is associated with sexual dysfunction, possibly making it difficult to separate illness effects from antidepressant side effects.
