A Percutaneous Endoscopic Gastrostomy, or PEG, tube is a soft, flexible tube placed through the abdominal wall directly into the stomach. Its main purpose is to provide nutrition, fluids, and medication to individuals who cannot safely swallow or eat by mouth. Administering medications through a PEG tube can be complex, and understanding proper procedures is important for patient safety and medication effectiveness.
Proper PEG Tube Medication Administration
Administering medication through a PEG tube requires careful attention. First, verify the medication order and prepare the correct dose. Liquid formulations are preferred. If a solid form is necessary, crush it into a fine powder and mix thoroughly with 15-30 mL of lukewarm water to prevent tube clogging.
Before administering any medication, flush the PEG tube with 15-30 mL of lukewarm water to ensure it is clear. Administer each medication separately to prevent interactions or clumping. After each dose, flush the tube again with 15-30 mL of water to ensure the full dose reaches the stomach.
Underlying Reasons Medications Cannot Be Given Through a PEG Tube
Medications may be unsuitable for PEG tube administration due to their design and interaction with the body or tube. A medication’s formulation dictates if it can be safely crushed or dissolved. Altering its physical form can destroy its intended release mechanism, leading to reduced effectiveness or an unsafe, rapid release of the entire dose.
Drug absorption can be compromised if the medication bypasses its intended absorption site. Some drugs require specific pH levels, like the stomach’s acidic environment, or need absorption in particular intestine sections. Administering them through a PEG tube into a different part of the gastrointestinal tract can prevent proper dissolution or absorption, rendering the medication ineffective.
Physical properties, such as viscosity or tendency to crystallize, can cause tube blockages. Viscous liquids or poorly dissolved powders can adhere to the tube’s inner walls, leading to occlusions. Some medications can also bind to the tube material, reducing the drug delivered.
Interactions between medications and tube feeding formulas are a concern. Mixing certain drugs directly with enteral formulas can lead to physical incompatibilities, such as precipitation or coagulation, which can clog the tube or alter drug bioavailability. Some medications or their excipients can also damage the tube or cause discomfort.
Specific Medication Forms to Avoid
Certain medication formulations are not suitable for PEG tube administration. These include:
- Enteric-coated medications (e.g., “EC,” “EN”): These have a special coating designed to prevent dissolution in stomach acid. This coating protects the drug from degradation or shields the stomach lining from irritation, ensuring the medication is released in the small intestine. Crushing them destroys the coating, leading to premature drug release, potential stomach irritation, and reduced effectiveness.
- Sustained-release, extended-release, or long-acting medications (e.g., “SR,” “XR,” “XL,” “CR,” “CD,” “LA”): Designed to release slowly over an extended period, crushing them can cause “dose-dumping,” where the entire dose is released at once. This can lead to dangerously high drug levels and increased side effects, also shortening the therapeutic effect, leaving the patient without adequate medication later in the dosing interval.
- Sublingual or buccal medications: Formulated to dissolve under the tongue or between the cheek and gum for rapid absorption directly into the bloodstream, bypassing the digestive system and liver metabolism. Administering them via a PEG tube bypasses their intended absorption route, which can significantly reduce their effectiveness.
- Effervescent tablets: Produce gas when dissolved, which can cause discomfort, bloating, or even damage to the PEG tube if administered directly.
- Chewable tablets: These are problematic because they are not designed to dissolve completely in liquid and can contain binders that, when crushed and mixed with water, may not create a fine enough suspension, leading to tube clogging.
- Capsules containing beads or pellets: While some immediate-release capsules can be opened and their contents mixed with water, many contain modified-release beads or enteric-coated granules. Crushing these beads can lead to dose-dumping or clumping that obstructs the tube.
- Viscous liquids or syrups: Their thick consistency can pose a clogging risk, particularly if not adequately diluted.
- Medications known to crystallize or precipitate: These can form solid particles when mixed with water or other solutions, blocking the tube. This can occur due to drug-drug incompatibilities or interactions between the medication and the diluent.
Actions to Take When a Medication Cannot Be Administered
When a medication is unsuitable for PEG tube administration, seek guidance from healthcare professionals. Consult the prescribing doctor to discuss alternative medication formulations or different medications that can be safely administered via the PEG tube or another route.
A pharmacist is a valuable resource. They have specialized knowledge of drug formulations, stability, and compatibility, and can advise if a medication can be safely altered or if an alternative product exists. Pharmacists can also suggest if a liquid formulation or a different tablet type is available that is more suitable for tube administration.
Exploring alternative routes of administration is another option, if medically appropriate and prescribed. This might include intravenous (IV) administration, transdermal patches, or rectal suppositories, depending on the drug and patient’s condition. These routes bypass the gastrointestinal tract, avoiding PEG tube administration issues.
Never alter medications without direct guidance from a healthcare professional. Manipulating medications not designed for PEG tube administration can lead to serious consequences, including reduced drug effectiveness, increased side effects, or tube damage. Patients and caregivers should seek clear instructions to ensure safe and proper medication administration.