What are suitable oral medication options for administration via a Percutaneous Endoscopic Gastrostomy (PEG) tube?

Oral Medications Suitable for PEG Tube Administration

Most oral medications can be administered via PEG tube if they are in liquid form or can be safely crushed, but each medication must be individually evaluated for appropriateness based on its formulation, site of delivery, and potential interactions with enteral formula. 1

General Principles for Medication Selection

Preferred Formulations

• Liquid formulations (suspensions, solutions, elixirs) are always preferred over solid dosage forms when available for PEG tube administration 2, 3
• Tablets that can be crushed and capsules that can be opened are acceptable alternatives when liquids are unavailable 3, 4
• Avoid liquid medications with osmolality >500-600 mOsm/kg as they can cause gastrointestinal disturbances 2

Medications That Should NOT Be Given via PEG Tube

• Extended-release or sustained-release formulations (crushing destroys the release mechanism) 3, 4
• Enteric-coated tablets (coating protects drug from gastric acid) 3, 4
• Sublingual or buccal medications (require mucosal absorption) 3
• Medications with specific absorption site requirements that differ from gastric delivery 1

Specific Medication Considerations

High-Risk Medications Requiring Special Attention

• Phenytoin: Binds directly to both enteral formula AND polyurethane feeding tubes; requires holding feeds 1-2 hours before and after administration 1, 3
• Carbamazepine: Requires special consideration for drug-nutrient interactions 3
• Warfarin: Potential interactions with enteral formula necessitate careful monitoring 3
• Fluoroquinolones: Drug-nutrient interactions may reduce efficacy 3
• Proton pump inhibitors: Special administration considerations required 3

Examples of Medications Successfully Studied for PEG Administration

• Lisinopril tablets: Can be crushed (contains mannitol, calcium phosphate, starch - all water-dispersible ingredients) 5
• Apixaban: Can be compounded as 0.25 mg/mL suspension in 50:50 Ora-Plus:water, stable for 7 days, compatible with polyurethane and PVC tubes 6
• Magnesium oxide: Can be crushed but requires careful technique as it is insoluble in water (only soluble in gastric acid) 7

Mandatory Administration Protocol

Step-by-Step Process

1. Confirm appropriateness: Verify the medication is suitable for PEG administration considering tube tip location (gastric vs. jejunal) and potential formula interactions 1

2. Consult pharmacy: Always consult a pharmacist before crushing any medication or administering through PEG tube 7, 2

3. Prepare medication properly:

   • Use mortar and pestle method for crushing (more accurate than pill crushers) 6
   • Dissolve crushed tablets in appropriate volume of water 4
   • Never mix multiple medications together 1

4. Flush protocol (critical to prevent occlusion):

   • Flush with 30 mL of water BEFORE medication 1
   • Administer medication individually 1
   • Flush with 30 mL of water BETWEEN each medication 1
   • Flush with 30 mL of water AFTER final medication 1

5. Use proper equipment: ENFit-standard syringes and connectors to prevent misconnection errors 7, 2

Critical Pitfalls to Avoid

• Never shake ENFit syringes to remove drug residue - this exposes personnel to medication and alters dosing 1, 7
• Never add medications directly to enteral formula - always administer separately 3
• Never mix medications together before administration - risk of drug-drug interactions and precipitation 1
• Do not assume all tablets can be crushed - 36 medications were identified as completely inappropriate for feeding tube administration in comprehensive evaluation 4
• Additional 46 medications are inappropriate for jejunal administration specifically (even if acceptable for gastric tubes) 4

Tube Material Considerations

• Polyurethane PEG tubes are preferable to silicone for medication administration due to better patency retention 1
• Certain medications (like phenytoin) bind to polyurethane tubes, requiring awareness and mitigation strategies 1

When Liquid Formulations Are Used

• Check osmolality before administration 2
• Be aware that elixirs may contain sorbitol, increasing risk of diarrhea 3
• Liquid formulations may still require dilution depending on viscosity 3