What are the common causes of drug-induced diarrhea in patients with a Jejunal (J)-tube?

Drug-Induced Diarrhea via Jejunal Tube

When diarrhea occurs in patients with J-tubes, immediately discontinue all laxatives and medications containing magnesium (including antacids) or sorbitol, as these are the most common and easily reversible causes of enteral feeding-associated diarrhea. 1

Primary Medication Culprits

Antibiotics (Most Common Drug Cause)

• Antibiotics account for 25% of all drug-induced diarrhea and have significantly higher incidence in patients receiving enteral tube feeding compared to those eating normally 1
• High-risk antibiotics include:
  • Penicillins (especially ampicillin) 1, 2
  • Clindamycin 1, 3
  • Cephalosporins 1
• Antibiotics alter intestinal flora, allowing pathogenic bacterial overgrowth and reducing colonic production of short-chain fatty acids 1
• Clostridium difficile toxin is found in 20-50% of patients with antibiotic-related diarrhea in tube-fed patients 1

Medications with Osmotic Effects

• Magnesium-containing antacids (magnesium trisilicate or hydroxide) 1, 4, 5
• Sorbitol-containing liquid medications - commonly used as inactive filler in liquid pharmaceutical preparations 1, 5
• Lactulose 5

Acid-Suppressing Medications

• H2 blockers 1
• Proton pump inhibitors (PPIs) 1
• These raise gastric pH, promoting bacterial overgrowth and increasing infection risk 1

Other High-Risk Drug Classes

• NSAIDs 1, 4
• Antiarrhythmics 1, 4
• Antihypertensives 1
• Colchicine - causes diarrhea in up to 77% of patients at high doses, 23% at therapeutic doses 6, 4
• Chemotherapy agents (particularly 5-FU, irinotecan, capecitabine) 1

Mechanism-Based Classification

Secretory Diarrhea

• Misoprostol, bisacodyl, chenodeoxycholic acid - activate adenylate cyclase causing active chloride and bicarbonate secretion 5

ATPase Pump Inhibition

• Digoxin, auranofin, colchicine, olsalazine - inhibit Na+/K+ exchange pump 5

Mucosal Damage

• Neomycin and colchicine - cause small intestine mucosal damage with fat malabsorption 5
• Gold salts and penicillamine - cause colitis of varying severity 5

Critical Management Steps

Immediate Actions

1. Stop all laxatives immediately 1
2. Review and discontinue medications containing magnesium or sorbitol 1
3. Send stool samples for Clostridium difficile toxins A and B - may require 2-3 repeat samples due to 63-99% sensitivity 1
4. Check for bacterial enteropathogens 1

Tube Feeding Considerations

• Diarrhea occurs in 10-60% of patients on enteral tube feeding, making it extremely common 1
• Jejunostomy tubes have higher clog rates (20-45%) and require more frequent flushing than gastrostomy tubes 7
• Formula osmolality and delivery rate contribute to diarrhea risk 1

Prevention Strategies

• Use liquid medications when possible rather than crushed tablets or syrups 8
• Establish medication compatibility before administration - hyperosmolar drugs and crushed tablets are particularly problematic 8
• Maintain strict aseptic technique - enteral feed is an ideal culture medium and contamination causes diarrhea, sepsis, and pneumonia 1
• Discard administration sets and nutrient containers every 24 hours 1

Common Pitfalls to Avoid

• Do not assume diarrhea is from the tube feed itself - it is often multifactorial with medications being the primary reversible cause 1
• Do not overlook medication excipients - lactose and sorbitol in pharmaceutical compounds can cause diarrhea even when the active ingredient is not typically associated with this side effect 1
• Do not delay stool testing - Clostridium difficile can occur after chemotherapy even without antibiotic exposure 1
• Remember that continuous feeding raises gastric pH - this promotes bacterial overgrowth and increases infection risk, particularly when combined with PPIs or H2 blockers 1