Bentyl (Dicyclomine) is NOT Recommended for Colitis
Bentyl (dicyclomine) should not be used for colitis and is contraindicated in severe ulcerative colitis. 1 The FDA drug label explicitly warns against its use in ulcerative colitis, and established inflammatory bowel disease guidelines do not include antispasmodic agents in the treatment algorithm for any form of colitis. 2
Why Dicyclomine is Inappropriate for Colitis
Direct Contraindications and Warnings
Dicyclomine is contraindicated in severe ulcerative colitis because large doses may suppress intestinal motility to the point of producing paralytic ileus and may precipitate or aggravate toxic megacolon, a life-threatening complication. 1
Caution is required even in non-severe ulcerative colitis, as the drug can worsen disease complications through its anticholinergic effects on gut motility. 1
Diarrhea may be an early symptom of incomplete intestinal obstruction, especially in patients with colostomy or ileostomy, making dicyclomine potentially harmful in inflammatory bowel disease. 1
Evidence-Based Treatment Guidelines for Colitis
The British Society of Gastroenterology guidelines for inflammatory bowel disease management provide clear treatment algorithms that do not include dicyclomine or any antispasmodic agents: 2
For Ulcerative Colitis:
- First-line therapy: Mesalazine 2-4 g daily or balsalazide 6.75 g daily for mild to moderate disease. 2
- Second-line therapy: Prednisolone 40 mg daily for moderate to severe disease or failed mesalazine therapy. 2
- Maintenance therapy: Long-term aminosalicylates, with azathioprine 1.5-2.5 mg/kg/day for steroid-dependent disease. 2
For Crohn's Colitis:
- Mild disease: High-dose mesalazine (4 g daily) as initial therapy. 2
- Moderate to severe disease: Oral prednisolone 40 mg daily. 2
- Refractory disease: Azathioprine, mercaptopurine, or infliximab. 2
Dicyclomine's Appropriate Use: IBS Only
Dicyclomine is indicated only for irritable bowel syndrome (IBS), not inflammatory bowel disease. 2, 3, 4, 5
The British Society of Gastroenterology guidelines for IBS list anticholinergic agents like dicyclomine as an option for abdominal pain in functional bowel disorders. 2
However, even for IBS, dicyclomine has not been proven effective in reducing abdominal pain in rigorous studies, and its use is limited by anticholinergic side effects. 5, 6
Critical Distinction: IBS vs. Colitis
The key clinical pitfall is confusing IBS with colitis:
IBS is a functional disorder with no inflammation, where antispasmodics may have a limited role. 2, 3
Colitis (ulcerative colitis, Crohn's colitis) involves active inflammation requiring anti-inflammatory therapy, where antispasmodics are contraindicated. 2, 1
NSAIDs can cause or exacerbate colitis, and similarly, anticholinergic agents can worsen inflammatory bowel disease through different mechanisms. 7
Safety Concerns with Dicyclomine
Beyond the contraindication in colitis, dicyclomine carries significant risks: 1
- Toxic megacolon risk when used in inflammatory bowel disease, particularly with Salmonella dysentery or ulcerative colitis. 1
- Intestinal pseudo-obstruction (Ogilvie's syndrome) has been reported. 1
- Anticholinergic side effects including constipation, urinary retention, confusion (especially in elderly), and heat prostration. 1
- Muscle cramps can occur as a documented side effect. 8