What medications can cause sticky feces?

Medications That Can Cause Sticky Feces

Opioids are the most common medications that cause sticky feces due to their significant effects on intestinal motility, resulting in constipation and changes in stool consistency. 1

Primary Medications Causing Sticky Feces

Opioids

• Opioids cause opioid-induced bowel dysfunction (OIC) through:
  • Decreased intestinal motility
  • Increased water absorption from stool
  • Reduced intestinal secretions
  • Examples: codeine, morphine, oxycodone 1, 2

Codeine specifically is known to cause constipation as a common side effect, which can manifest as sticky feces 2. It works by slowing fluid movement through the jejunum, increasing contact time with mucosal cells and enhancing water absorption 3.

Anticholinergic Medications

• Reduce intestinal motility and secretions
• Examples:
  • Tricyclic antidepressants
  • Antihistamines (especially first-generation)
  • Antipsychotics
  • Antispasmodics (dicyclomine, hyoscine butylbromide) 1

Calcium Channel Blockers

• Decrease smooth muscle contractility in the intestines
• Can lead to constipation and sticky stool 1

Other Common Medications

• Iron supplements (particularly ferrous sulfate)
• Antacids containing aluminum or calcium
• Antiemetics (especially those with anticholinergic properties)
• Certain psychiatric medications 1, 4

Mechanisms and Management

How Medications Affect Stool Consistency

1. Decreased motility: Slower transit time allows more water absorption
2. Reduced secretions: Less fluid in the intestinal lumen
3. Altered gut microbiome: Can change stool consistency and composition
4. Bile salt malabsorption: Can occur with certain medications affecting terminal ileum function 1, 5

Management Strategies

For Opioid-Induced Sticky Feces

• Prophylactic laxative therapy should be initiated when starting opioids 1
• Preferred options:
  • Stimulant laxatives (senna, bisacodyl) 1
  • Osmotic laxatives (polyethylene glycol, lactulose) 1
• For refractory cases, consider:
  • Peripherally acting μ-opioid receptor antagonists (PAMORAs) such as methylnaltrexone or naloxegol 1, 6
  • Combined opioid/naloxone medications 1

For Other Medication-Induced Sticky Feces

• Adequate hydration (1-2 liters daily)
• Dietary modifications (increased fiber if appropriate)
• Consider medication alternatives when possible
• Avoid bulk-forming laxatives in severe cases 1

Special Considerations

Small Intestinal Bacterial Overgrowth (SIBO)

Some medications can contribute to SIBO, which may present with sticky feces:

• Proton pump inhibitors (reduce gastric acid)
• Opioids (slow motility)
• Treatment may include:
  • Rifaximin (first-line antibiotic)
  • Low-FODMAP diet
  • Prokinetics to improve motility 5

Faecal Impaction

In severe cases, medications can lead to faecal impaction:

• Management involves:
  • Digital fragmentation if necessary
  • Enemas or suppositories
  • Prevention with maintenance bowel regimen 1

Clinical Pitfalls to Avoid

1. Failing to recognize medication-induced constipation: Always review medication list when evaluating sticky feces
2. Using bulk laxatives for opioid-induced constipation: These are specifically not recommended and may worsen symptoms 1
3. Overlooking the need for prophylactic laxatives: All patients on opioids should receive preventive treatment 1
4. Ignoring underlying conditions: Some patients may have pre-existing motility disorders exacerbated by medications
5. Inadequate dosing of laxatives: Higher doses may be needed (e.g., loperamide 12-24 mg at a time for short bowel) 1

By recognizing medications that cause sticky feces and implementing appropriate management strategies, clinicians can significantly improve patient comfort and quality of life.