Purpose: An overview of enteral feeding tubes, drug administration techniques, considerations for dosage form selection, common drug interactions with enteral formulas, and methods to minimize tube occlusion is given.
Summary: Enteral nutrition through a feeding tube is the preferred method of nutrition support in patients who have a functioning gastrointestinal tract but who are unable to be fed orally. This method of delivering nutrition is also commonly used for administering medications when patients cannot swallow safely. However, several issues must be considered with concurrent administration of oral medications and enteral formulas. Incorrect administration methods may result in clogged feeding tubes, decreased drug efficacy, increased adverse effects, or drug-formula incompatibilities. Various enteral feeding tubes are available and are typically classified by site of insertion and location of the distal tip of the feeding tube. Liquid medications, particularly elixirs and suspensions, are preferred for enteral administration; however, these formulations may be hypertonic or contain large amounts of sorbitol, and these properties increase the potential for adverse effects. Before solid dosage forms are administered through the feeding tube, it should be determined if the medications are suitable for manipulation, such as crushing a tablet or opening a capsule. Medications should not be added directly to the enteral formula, and feeding tubes should be properly flushed with water before and after each medication is administered. To minimize drug-nutrient interactions, special considerations should be taken when administering phenytoin, carbamazepine, warfarin, fluoroquinolones, and proton pump inhibitors via feeding tubes. Precautions should be implemented to prevent tube occlusions, and immediate intervention is required when blockages occur.
Conclusion: Successful drug delivery through enteral feeding tubes requires consideration of the tube size and placement as well as careful selection and appropriate administration of drug dosage forms.