What Is IBS?

Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder characterized by recurrent abdominal pain associated with changes in bowel habits. It is defined by the presence of symptoms without visible signs of damage or disease in the digestive tract. IBS is categorized into subtypes based on predominant stool pattern: diarrhea‑predominant (IBS‑D), constipation‑predominant (IBS‑C), mixed (IBS‑M), or unclassified.

Symptoms

• Abdominal pain or cramping, often relieved or worsened after bowel movements.
• Bloating or excess gas.
• Diarrhea, constipation, or alternating between the two.
• A sensation of incomplete bowel movements.

Causes and Triggers

• The exact cause of IBS is unknown; factors may include gut motility problems, heightened pain sensitivity, and imbalances in gut bacteria.
• Post‑infectious changes after a gastrointestinal infection.
• Stress and emotional factors can exacerbate symptoms.
• Certain foods (high FODMAPs, dairy, caffeine, artificial sweeteners) can trigger or worsen symptoms.

Diagnosis

• IBS is diagnosed based on symptom criteria (such as Rome IV) and the exclusion of other conditions.
• Your provider may order blood tests, stool tests, or endoscopic procedures to rule out inflammatory bowel disease, celiac disease, or other disorders.
• No single test confirms IBS; a thorough medical history and physical exam are essential.

Management

• Dietary changes: Following a low FODMAP diet, increasing soluble fiber for IBS‑C, and avoiding trigger foods.
• Medications: Antispasmodics for cramping, antidiarrheal agents, laxatives, or prescription medications such as rifaximin, eluxadoline, lubiprostone, or linaclotide based on your subtype.
• Probiotics: May improve symptoms in some patients.
• Behavioral therapies: Stress reduction techniques, cognitive behavioral therapy, and regular exercise can help manage symptoms.

IBS is a chronic condition, but with a tailored treatment plan, many patients achieve good symptom control and maintain a high quality of life.