Invited commentary
Newer antidepressants in irritable bowel syndrome: what is the evidence?Commentary on
Selective serotonin reuptake inhibitors for the management of irritable bowel syndrome: a meta-analysis of randomized controlled trials
Roja Rahimi, Shekoufeh Nikfar, Mohammad Abdollahie

Irritable bowel syndrome (IBS) is a chronic unexplained condition characterized by abdominal discomfort or pain that is intimately linked to disturbed defecation; bloating is a common accompanying symptom [1, 2]. Specific symptom-based criteria have been identified for the syndrome, and a positive diagnosis is possible based on taking an adequate medical history [1-3]. Multiple deranged pathophysiological mechanisms have been identified in this condition, including abnormalities of gut transit and sensation, but whether the motility abnormalities arise primarily from within the gastrointestinal tract or in the central nervous system, or both, remains unclear [2, 3]. There is general agreement that the brain/gut axis is disturbed in IBS, and drugs that modulate this axis theoretically may be able to reduce symptomatology [3]. In patients who fail first line gut directed therapy for IBS, a trial of antidepressant treatment is often considered as a reasonable next step in clinical practice [2, 3]. It is established that the tricyclic antidepressants can slow intestinal transit and therefore may be particularly useful in patients with diarrhea-predominant IBS [4]. Alternatively, the selective serotonin reuptaking inhibitor (SSRI) drug class can accelerate colonic transit [4]; this drug class reduces reuptake of serotonin by the gut serotonin transporter, leading to accumulation of serotonin in the neuroenteric system that can stimulates peristalsis. Therefore, pharmacologically it makes sense to consider targeting patients with constipation predominant IBS using the SSRI drug class. The SSRI’s are also often better tolerated than the tricyclic antidepressants, and have anxiety reducing benefits that may also be potentially of value in IBS [5]. In this issue of the Journal, Rahimi et al., report the results of a meta-analysis limited to evaluating the efficacy of SSRI’s in IBS; overall, SSRIs were not significantly better than placebo for the relief of individual IBS symptoms [6]. Little data have been published on SSRIs in IBS. Despite a comprehensive search, the authors of this meta-analysis found only five randomized placebo-controlled trials that they could include. This resulted in a total of just 147 women and 74 men with IBS who were randomized to either an SSRI or placebo. While the available data on SSRI use in IBS is still remarkably limited, the absence of evidence for a benefit does not mean there is no benefit, and looking at the...


View full text...