What is the recommended treatment and dosage for irritable bowel syndrome (IBS) using Mebeverine?

Mebeverine for Irritable Bowel Syndrome

Mebeverine is a first-line antispasmodic option for IBS that can effectively treat global symptoms and abdominal pain, dosed at 135 mg three times daily (standard formulation) or 200 mg twice daily (sustained-release formulation), though it is positioned behind soluble fiber and lifestyle modifications in treatment algorithms and has modest efficacy compared to tricyclic antidepressants. 1, 2

Treatment Algorithm Position

First-Line Approach (Before Mebeverine)

• Start with lifestyle modifications: Regular exercise should be advised to all IBS patients as the initial intervention 1
• Implement dietary therapy: Soluble fiber (ispaghula) at 3-4 g/day, gradually increased to avoid bloating, is more strongly recommended than antispasmodics for global symptoms and abdominal pain 1
• Consider mebeverine as a first-line pharmacologic option when lifestyle and dietary measures are insufficient, recognizing that certain antispasmodics may be effective but with very low quality evidence 1

When to Use Mebeverine

• Mebeverine is appropriate for patients with abdominal pain and spasms who have not responded adequately to exercise and dietary fiber 2
• The British Society of Gastroenterology notes that antispasmodics (including mebeverine) may help global symptoms and abdominal pain, though common side effects like dry mouth, visual disturbance, and dizziness can limit tolerability 1

Dosing Regimens

Standard Formulation

• 135 mg three times daily before meals is the traditional dosing schedule 3, 4
• This formulation demonstrated effectiveness in over 80% of patients in controlled trials, with 33% achieving complete symptom resolution after 6 weeks 3

Sustained-Release Formulation

• 200 mg twice daily provides equivalent efficacy to the standard formulation while reducing dosing frequency 3
• The sustained-release form showed 18% complete symptom resolution after 6 weeks in the first treatment period, increasing to 40% after crossover 3
• In IBS with diarrhea specifically, 200 mg controlled-release twice daily for 8 weeks showed modest but statistically significant improvement in bowel movements, cramps, and quality of life, though intergroup differences versus placebo were not significant 5

Efficacy Profile

Symptom Improvements

• Abdominal pain reduction: Six studies in a systematic review reported significant decreases in abdominal pain (p-values <0.05 to <0.001) 2
• Additional benefits: Improvements in abnormal bowel habits, abdominal distension, stool frequency and consistency have been documented 2
• Quality of life: Mean QOL scores improved from 106 to 95 after 6 weeks of treatment in one comparative trial 6

Limitations to Consider

• Modest efficacy in severe IBS-D: Mebeverine will not be a good choice for patients with severe diarrhea-predominant symptoms, as the effect size is modest 5
• Three studies showed no improvement in abdominal pain or discomfort severity, indicating variable response 2
• Less effective than tricyclic antidepressants: For patients requiring second-line therapy, tricyclic antidepressants (starting at 10 mg amitriptyline, titrating to 30-50 mg daily) have stronger evidence (moderate quality) compared to antispasmodics (very low quality evidence) 1

Safety Profile

Tolerability

• Adverse events are rare and mainly associated with underlying IBS symptoms rather than the medication itself 2
• No worsening of symptoms or side effects were observed in a 6-week comparative trial 6
• Compliance approaches 100% for most patients, particularly with the sustained-release formulation 3

Common Pitfalls

• Anticholinergic side effects (dry mouth, visual disturbance, dizziness) are listed as common with antispasmodics in general, though mebeverine specifically appears better tolerated than other agents in this class 1
• Palatability issues: When combined with ispaghula in fixed combination, up to 28% of patients found the treatment unpalatable, suggesting mebeverine alone or with separate fiber supplementation is preferable 4

Comparative Effectiveness

• Similar efficacy to other antispasmodics: Mebeverine showed comparable effectiveness to trimebutine (100 mg twice daily), though trimebutine demonstrated superior quality of life improvements 6
• Combination with fiber: Mebeverine plus high-fiber dietary advice showed no significant advantage over mebeverine plus ispaghula, but the dietary advice approach had better acceptability 4
• Position relative to other options: Mebeverine is best reserved for intermittent use during pain flares rather than chronic daily therapy, similar to the positioning of dicyclomine 7