Irritable bowel syndrome (IBS)

Irritable bowel syndrome (IBS) is the most common functional disorder of the gastrointestinal tract. The condition causes varying symptoms, most often in the form of diarrhea, constipation, or an alternation between the two. IBS is considered a disturbance of intestinal motility (movement), without any detectable organic disease or injury in the bowel¹.

Image: “3D medical animation still showing irritable bowel syndrome” by Scientific Animations, from Scientific Animations wiki images, via Wikimedia Commons (https://commons.wikimedia.org/wiki/File:Irritable_bowel_syndrome.jpg), licensed under Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) – https://creativecommons.org/licenses/by-sa/4.0/.

Causes

The exact cause of IBS remains unknown despite extensive research. It is believed that multiple factors interact. In recent years, a common protozoan, Blastocystis sp., has gained increased attention as a potential triggering factor. However, the mechanism by which this microorganism may contribute to IBS is still unclear².

Epidemiology

IBS is one of the most frequently diagnosed conditions in primary care. About 12% of patients who visit their general practitioner do so due to IBS-related symptoms¹³. Prevalence varies by region and diagnostic criteria but ranges globally between 7% and 21%²⁴. The highest prevalence has been reported in South America (~21%), while Southeast Asia has the lowest (~7%).

Clinical presentation

The symptoms of IBS are variable, often intermittent, and mainly include:

• Abdominal pain and cramps (especially in the lower left quadrant)

• Constipation

• Diarrhea

• Abdominal bloating and flatulence

• Nausea and vomiting

• Loss of appetite and weight loss

• Foul-smelling breath and acid reflux

• White mucus in stool

The pain is often described as aching and deep, with acute cramps. It commonly occurs in the morning or after meals and is often relieved after defecation³.

Diagnosis

IBS is a diagnosis of exclusion, as no objective findings confirm the condition. Diagnosis is based on patient history and the use of symptom criteria:

Rome III criteria⁵:

• Abdominal pain at least three days per month during the last three months

• Improvement after defecation

• Change in stool frequency

• Change in stool consistency

Manning criteria⁵:

• Pain relief after defecation

• Sensation of incomplete evacuation

• Mucus in stool

• Changes in bowel habits

Additional investigations that may be relevant:

• Rectoscopy/colonoscopy to exclude serious conditions

• Stool tests and blood tests (e.g., for celiac disease)⁵

Differential diagnoses

Because IBS symptoms resemble several serious conditions, differential diagnostics must be thorough. The following should be considered and excluded:

• Ulcerative colitis – inflammation of the colonic mucosa

• Crohn’s disease – may affect the entire gastrointestinal tract

• Celiac disease – autoimmune reaction to gluten

• Colorectal cancer¹⁴

Treatment and follow-up

The goal of treatment is to reduce symptoms and improve quality of life. Treatment is always symptom-driven and includes:

Pharmacological treatment:

• For constipation: dietary fiber and mild laxatives

• For diarrhea: loperamide and probiotics

• The antibiotic rifaximin has shown good effect in diarrhea³

• Antidepressants in low doses (TCA or SSRI) for pain or concurrent psychological distress⁴

Dietary measures:

• Eliminate known triggers (e.g., cabbage, carbonated drinks, raw fruit)

• Reduce intake of FODMAPs (fermentable carbohydrates)

• Consider lactose and gluten reduction if intolerance is suspected

Lifestyle and psychosocial treatment:

• Stress management and relaxation techniques

• Psychotherapy or cognitive behavioral therapy

• Biofeedback or hypnosis in severe cases³

Probiotics:

• Bifidobacterium infantis has shown positive effect, while other strains have varying evidence

The physiotherapist’s role

Although IBS is not primarily treated with physiotherapy, physiotherapists can play an important supportive role:

1. Activity and bowel functionRegular physical activity promotes intestinal peristalsis and reduces constipation. It also reduces stress, which is central in IBS.

2. Breathing and stress responseSome patients develop hyperventilation or breath-holding in stressful situations. The physiotherapist can guide breathing techniques to alleviate this.

3. Trauma-informed approachWomen with IBS often have a background of trauma or abuse. Physiotherapists, particularly in women’s health, should be aware of this association and provide information about relevant support services³.

References

1. Goodman CC, Snyder TE. Differential Diagnosis for Physical Therapists: Screening for Referral. 5th ed. St. Louis: Saunders Elsevier, 2013.

2. Radiopaedia. Irritable Bowel Syndrome. Available from: https://radiopaedia.org/articles/irritable-bowel-syndrome?lang=us (accessed 05.07.2025)

3. Goodman CC, Fuller KS. Pathology: Implications for the Physical Therapist. 4th ed. St. Louis: Saunders Elsevier, 2015.

4. Patel N, Shackelford K. Irritable Bowel Syndrome. [Updated July 10]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls. Available from: https://www.ncbi.nlm.nih.gov/books/NBK534810/ (accessed 05.07.2025)

5. Ringström G, Störsrud S, Lundgvist S, Westman B, Simrén M. Development of an educational intervention for patients with irritable bowel syndrome: A pilot study. BMC Gastroenterology. 2020;9(10):1–9.

6. Mayo Clinic. Irritable Bowel Syndrome. Available from: http://www.mayoclinic.com/health/irritable-bowel-syndrome/DS00106/DSECTION=prevention (accessed 05.07.2025)