What bowel regimen can be administered through a Nasogastric (NG) tube?

Bowel Regimens That Can Be Administered Through an NG Tube

Polyethylene glycol (PEG) and senna are the most effective bowel regimens that can be safely administered through a nasogastric (NG) tube. 1, 2

Suitable Bowel Regimen Options for NG Tube Administration

First-Line Options:

1. Polyethylene Glycol (PEG) 3350

   • Standard dose: 17g dissolved in water 1
   • Can be administered as a liquid solution through fine bore NG tubes (5-8 French gauge) 3
   • Advantages: Effective, non-stimulant laxative with minimal systemic absorption
   • Administration: Dissolve completely in water before administration

2. Senna

   • Available as liquid formulation suitable for NG tube administration 2
   • Stimulant laxative that works by increasing intestinal motility
   • Effective for opioid-induced constipation 4

3. Combination of Low-Volume PEG and Senna

   • More effective with fewer side effects than high-volume PEG alone 5
   • The combination provides both osmotic and stimulant effects
   • Reduces abdominal pain compared to high-dose senna alone 6

Administration Guidelines

General Principles:

• Any drugs administered via an NG tube should be in liquid form 3
• Medications should be given separately from enteral feeds 3
• Always flush the tube before and after medication administration to prevent clogging 3

Administration Protocol:

1. Verify tube placement before administering any medication using pH testing 3
2. Temporarily stop enteral feeding before medication administration
3. Flush with 30ml water before medication administration
4. Administer liquid medication (ensure complete dissolution if using powder forms)
5. Flush with 30ml water after medication administration
6. Resume feeding after appropriate interval

Important Considerations

Tube Type and Size:

• Fine bore (5-8 French gauge) NG tubes can accommodate most liquid medications 3
• Avoid high-viscosity preparations that may clog smaller tubes 3

Medication Formulation:

• Use liquid formulations whenever possible
• If using PEG powder, ensure complete dissolution in adequate water
• Never crush enteric-coated or sustained-release tablets

Monitoring and Complications:

• Monitor for gastric residual volumes; if aspirates exceed 200ml, review feeding and medication policy 3
• To minimize aspiration risk, keep patient propped up at least 30° during and for 30 minutes after administration 3
• Watch for potential side effects: abdominal cramping, nausea, diarrhea 4, 5

Special Situations

For Patients with Limited Gastric Motility:

• Consider checking gastric residual volume every 4 hours 3
• May need to adjust dosing or switch to prokinetic agents

For Long-term NG Tube Placement:

• Change NG tubes every 4-6 weeks, alternating nostrils 3
• Consider gastrostomy if NG feeding is likely to continue beyond 4-6 weeks 3

Evidence-Based Efficacy

Research shows that senna-based protocols are effective for managing constipation, with one study demonstrating that a sennosides-only protocol produced more bowel movements than a sennosides plus docusate protocol 4. Additionally, the combination of low-volume PEG with senna has been shown to be equally effective as high-volume PEG alone, but with fewer side effects like nausea, bloating, and headache 5, 6.