Published online by Cambridge University Press: 07 November 2014
Four years ago, my colleagues and I published an article titled “Why isn't bupropion the most frequently prescribed antidepressant?” The goal of that article was not to advocate bupropion as the preferred agent for treating depression, but rather to stimulate discussion about how psychiatrists choose an antidepressant as well as to highlight the gap between results of efficacy studies and clinical decision making in real-world practice.
The argument in support of bupropion being the preferred antidepressant was based on three premises: all antidepressants are equally effective; adverse effects (AEs) of greatest concern to patients who take antidepressants are weight gain and sexual dysfunction; and bupropion does not cause either of these AEs. Acceptance of these three premises suggested the title of that article.
Although many reviews of the antidepressant literature, including the revised American Psychiatric Association Practice Guideline for the Treatment of Major Depressive Disorder, conclude that antidepressants are equally effective in general, several experts in the treatment of depression have suggested that medications with >1 mechanism of action may be more effective than agents that have more selective neurotransmitter effects. In a meta-analysis of eight studies comparing the remission rates in patients treated with the serotonin-norepinephrine reuptake inhibitor (SNRI) venlafaxine or selective serotonin reuptake inhibitors (SSRIs), Thase and colleagues demonstrated that venlafaxine was more effective than SSRIs in achieving remission in depressed patients. However, these conclusions were tentative as most of the included studies were comparisons of venlafaxine and fluoxetine; only one study included sertraline, and there were no studies of citalopram included in the review. In addition, patients who had previously failed treatment with an SSRI were not excluded, and, although patients who fail with one SSRI may respond to subsequent treatment with another SSRI, the inclusion of SSRI failures may favor venlafaxine in comparisons with SSRIs. Lastly, all of the studies included in the meta-analysis were funded by the manufacturer of venlafaxine.