Bulk forming agents

Bulk-forming laxative agents include:

• bran
• ispaghula husk
• methylcellulose
• sterculia granules

Bulk-forming laxatives:

• have been shown to decrease abdominal pain and improve stool consistency
• bulk-forming laxatives they are only required if dietary fibre cannot be increased sufficiently - an effective bulk-forming preparation is unprocessed wheat bran (taken with food or fruit juice)
• not appropriate for acute relief, as they may take several days to work, but they are a good option for long-term control
• bulk-formng agents increase stool bulk. The increased stool bulk then stimulates peristalsis. Clearly to prevent obstruction, fluid intake must be maintained
• it is essential to drink adequate amounts of fluid when using bulk-forming laxatives to avoid intestinal obstruction.
• flatulence and abdominal distension are the most common side effects.

Bulk forming laxatives are contraindicated in patients with existing bowel obstruction or faecal impaction.

Reference:

1. MeReC Bulletin 2004 ; 14(6): 21-4.