Overview
Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder affecting the large intestine. It causes recurring abdominal pain and changes in bowel habits without any structural damage to the gut. While not life-threatening, IBS can significantly affect quality of life. It affects women more than men and typically begins before age 50. Symptoms vary widely between individuals and can fluctuate over time.
Causes and risk factors
The following factors are associated with the development of Irritable Bowel Syndrome (IBS):
- Abnormal gut motility
- Visceral hypersensitivity of gut nervous system
- Changes in gut microbiome
- Post-infectious IBS following gastroenteritis
- Food sensitivities, particularly to FODMAPs
- Stress and psychological factors
- Hormonal factors
- Genetic predisposition
- Early life stress or trauma
Signs and symptoms
Common signs and symptoms of Irritable Bowel Syndrome (IBS) include:
- Abdominal pain or cramping relieved by bowel movements
- Bloating and flatulence
- Diarrhoea (IBS-D)
- Constipation (IBS-C)
- Alternating diarrhoea and constipation (IBS-M)
- Mucus in stool
- Urgency to open bowels
- Sensation of incomplete emptying
- Nausea
Diagnosis
Irritable Bowel Syndrome (IBS) is typically diagnosed through a combination of medical history, physical examination, and appropriate investigations such as blood tests, imaging, or specialist review, depending on the specific condition and presentation. Your doctor will consider all relevant symptoms and risk factors before making a diagnosis.
Treatment options
Treatment approaches for Irritable Bowel Syndrome (IBS) may include:
- Low-FODMAP diet
- Increased soluble fibre for IBS-C
- Antispasmodics (mebeverine) for cramps
- Loperamide for diarrhoea
- Osmotic or bulk-forming laxatives for IBS-C
- Low-dose antidepressants for pain modulation
- Peppermint oil capsules
- Gut-directed hypnotherapy
- Probiotics
- Stress management and CBT
Prevention
Regular meals, avoiding trigger foods, staying hydrated, reducing stress, exercising regularly, and adequate sleep.
Complications
If left untreated or poorly managed, Irritable Bowel Syndrome (IBS) can lead to complications including:
Anxiety, depression, social isolation, and impact on work and daily life. Does not increase cancer risk.
Sources and references: This article is written in accordance with NHS UK, WHO, and Mayo Clinic clinical guidelines. It is reviewed for accuracy by the SymptomSense content team. ICD-10 code: K58. Last reviewed June 2026.