Irritable Bowel Syndrome (IBS) Treatment & Management

Updated: Feb 15, 2022
  • Author: Jenifer K Lehrer, MD; Chief Editor: BS Anand, MD  more...
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Approach Considerations

Management of irritable bowel syndrome consists primarily of providing psychological support and recommending dietary measures. Pharmacologic treatment is adjunctive and should be directed at symptoms, such as modulation of persistent visceral hyperalgesia. [10]

The 2009 American College of Gastroenterologists (ACG) position statement recommends addressing nongastrointestinal symptoms and comorbidities to improve health-related quality of life as well as to reduce symptom severity. Evidence considered in the position statement was insufficient to recommend exclusion diets or food allergy testing. [3]

The 2014 ACG monograph on the management of irritable bowel syndrome and chronic idiopathic constipation found insufficient evidence to recommend prebiotics or synbiotics, or loperamide, in irritable bowel syndrome, and no evidence that polyethylene glycol improved overall symptoms and pain in affected patients. [32] There was high quality of evidence to support the use of antidepressants as a class, and moderate quality of evidence in favor of fiber and psyllium, for overall symptomatic relief in irritable bowel syndrome. Strong recommendations were reported for linaclotide and lubiprostone each being superior to placebo in treating the constipation-predominant disease subtype. [32]

Successful management relies on a strong patient-provider relationship. Reassure the patient that the absence of an organic pathology indicates a normal life expectancy. Emphasize the expected chronicity of the symptoms with periodic exacerbations. Teach the patient to identify stressors and to use avoidance techniques.

Frequent visits with the clinician enhance the patient-provider relationship, especially in patients who were recently diagnosed with irritable bowel syndrome. Visits can become less frequent as patients are educated and reassured.


Dietary Measures

Fiber supplementation may improve symptoms of constipation and diarrhea. Individualize the treatment because a few patients experience exacerbated bloating and distention with high-fiber diets. Polycarbophil compounds (eg, Citrucel, FiberCon) may produce less flatulence than psyllium compounds (eg, Metamucil).

The data regarding the effectiveness of fiber are controversial because 40-70% of patients improve with placebo. A Cochrane systematic review found no benefit of fiber/bulking agents on irritable bowel syndrome symptoms or global assessment. [33]

Judicious water intake is recommended in patients who predominantly experience constipation.

Caffeine avoidance may limit anxiety and symptom exacerbation. Legume avoidance may decrease abdominal bloating. Lactose and/or fructose should be limited or avoided in patients with these contributing disorders. Take care to supplement calcium in patients limiting their lactose intake.

Gluten intolerance has been associated with irritable bowel syndrome. In a small but important study, patients with irritable bowel syndrome who were well-controlled on a gluten-free diet were rechallenged in a double-blind fashion. [34] Approximately two thirds of these patients had poor symptom control with rechallenge. As with many irritable bowel syndrome studies, the placebo response was high (40%). Notably, neither intestinal inflammation nor permeability was different among the groups, and no difference in the positivity rate for celiac disease–related HLA haplotypes or antibody markers was noted. Volta et al evaluated the current evidence and suggest that patients with gluten/wheat sensitivity may be a subset of those with irritable bowel syndrome. [35]

Many patients are interested in dietary manipulation to decrease their symptoms. Several different diets have been proposed. [36] Diets low in FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols) hold particular interest in reducing symptoms of irritable bowel syndrome. [37] Investigators found 10 of 54 bacterial markers differed significantly between 32 patients who responded to FODMAPs and 29 who did not; using their findings, they developed a response index that assesses gut microbial composition and has the potential to identify patients who are more likely to respond to a dietary FODMAP restriction. [38] In a preclinical, murine study, a low-FODMAP diet did not appear to exacerbate nor mitigate inflammation on a postinflammatory model of IBS. [39] However, a retrospective study (2013-2016) comprising data from 164 Irish patients with IBS found that a low-FODMAP diet provided significant all-symptomatic improvement at 3-, 6-, and 12-month follow-up. [40]

Probiotics are very interesting for treating symptoms, but it is unclear for which patients probiotics are helpful, and in what form, dose, combination, or strain. [41, 42, 43] A meta-analysis concluded that Bifidobacterium infantis may help alleviate some symptoms of irritable bowel syndrome. [44]

A systematic review and meta-analysis of 13 articles that assessed the differential expression of intestinal microbiota in 360 patients with this condition compared to 268 healthy controls found downregulation of bacterial colonization of Lactobacillus, Bifidobacterium, and Faecalibacterium prausnitzii in patients with irritable bowel syndrome. [45] Those with the diarrhea-predominant subtype had significantly different expression of Lactobacillus and Bifidobacterium. A different systematic review and meta-analysis evaluated 43 articles on probiotics and showed that probiotics helped relieve pain, bloating, and gas [46] ; however, again, it remains unknown which probiotic is the best.

A European multicenter pilot study that evaluated the effectiveness of palmitoylethanolamide/polydatin in 54 patients with irritable bowel syndrome compared to 12 healthy controls did not show any significant changes in modifying the biologic profile of the condition (eg, mast cell count); however, this combination significantly improved the severity of abdominal pain when compared to placebo. [47]

In a study of 998 adolescent Iranian girls, investigators noted a 16.9% prevalence of irritable bowel syndrome and identified several factors that appeared to be associated with an increased risk of this condition, including intrameal fluid consumption, consumption of spicy and fried food, insufficient chewing, and greater loss of teeth (≥5 teeth). [48]


Psychological Therapy

Consider psychiatric referral. Previous evidence supported improvement in gastrointestinal (GI) symptoms with successful treatment of psychiatric comorbidities, but studies by Zijdenbos et al and Ford et al indicate that caution should be used when interpreting such data. [49, 50]

In a meta-analysis by Zijdenbos et al of 25 randomized trials consisting of single psychological interventions with usual care or mock intervention in patients older than 16 years, the authors found that although cognitive-behavioral therapy and interpersonal psychotherapy were effective immediately after treatment completion, there was no convincing evidence for sustained benefits with any treatment modality. Thus, Zijdenbos et al recommended that future research should focus on current irritable bowel syndrome treatment guidelines and their long-term effects. [49]

Ford et al reached similar conclusions regarding the use of psychological interventions in irritable bowel syndrome. The authors concluded that antidepressants are effective in the treatment of irritable bowel syndrome, but although the available data suggest that psychological therapies may be of comparable efficacy, there is less high-quality evidence for the routine use of psychological therapies in patients with IBS. They performed a systematic review and meta-analysis of randomized controlled trials in adults with IBS; however, their selection criteria included trials comparing antidepressants with placebo as well as those comparing psychological therapies with control therapy or usual care. The investigators noted that the quality of studies were generally good for those involving antidepressants but poor for those involving psychological therapy. [50]

A Cochrane systematic review determined that antidepressants improved both irritable bowel symptoms and global assessment scores compared with placebo. Selective serotonin reuptake inhibitors (SSRIs) and tricyclic antidepressants were both shown to be effective in subgroup analyses. [33]

The 2009 American College of Gastroenterologists (ACG) position statement concluded that psychological interventions, cognitive behavioral therapy, dynamic psychotherapy, and hypnotherapy, are more effective than placebo. Relaxation therapy was no more effective than usual care. In agreement with the above analysis, study quality was described as low. [3]

More recent studies suggest targeting the mediating psychological process involved in patients with irritable bowel syndrome, such as illness perceptions, maladaptive coping, and visceral sensitivity. [24]