A Stepwise Approach: Selecting Meds for Feeding Tube Administration

Step 1: Initial Evaluation of Meds

Question

Considerations^1-6,8,9,17

Is the med necessary?

Evaluate patient med lists for drugs that are no longer necessary and discontinue them.

Consider how long the tube will be in place. Is it possible to “hold” some meds temporarily?

Is there a more appropriate alternative med?

Consider alternative medications that may be equally effective and more appropriate for administration via a feeding tube (e.g., an alternative med may be available as a liquid or a nonoral formulation).

Is the med or an alternative available in a nonoral form?

Nonoral options may include buccal, intramuscular (IM), intravenous (IV), rectal, sublingual, topical, or transdermal.

Some injectable meds can be given orally or through a feeding tube (e.g., acetylcysteine, vancomycin, vitamin K). See our chart, Giving Meds by Alternative Routes, for these and other possibilities (e.g., oral meds given rectally).

Generally, buccal and sublingual routes are okay to use in a patient with a feeding tube. DO NOT administer these meds via a feeding tube as they may be ineffective.

Is there a liquid or suspension formulation of the med? If yes…

Generally, dilute any liquid med immediately before administration with 10 to 30 mL of sterile water.

Consider bioavailability differences to determine if different dosing is needed between liquids and tablets (e.g., digoxin).²

Check suspensions for granule size as some large, suspended particles can clog tubes.²

Syrups are generally more likely to clump with enteral nutrition compared to elixirs and suspensions.¹⁵

Consider sorbitol content of ALL liquid meds when calculating total daily sorbitol given:

Consider sugar content when using liquid meds for patients with diabetes.

Consider osmolality (typically found in product labeling).

If the med is only available as a tablet or capsule, can the tablet be crushed or can the capsule be opened and given through an enteral feeding tube?

Tablets that should generally NOT be crushed include:

Some capsules that contain microencapsulated pellets can be opened, and the intact pellets can be administered through large-bore feeding tubes. (Five to 12 French tubes are considered small-bore and ≥14 French are considered large-bore tubes.) Use our chart, Medications That Should Not Be Crushed, as a reference.

When giving tablets through a feeding tube, crush to a fine powder and mix with 10 to 15 mL of water immediately prior to administration. Some powders may settle quickly, so shake well immediately prior to administration.¹⁵

Proton pump inhibitors (PPIs) are a special case. They are acid labile and absorbed in the intestine. PPIs are formulated to protect the drug as it moves through the acidic environment of the stomach. The following Rx PPI formulations can be administered through a nasogastric (NG) tube (check product labeling for restrictions and specific instructions):

Is the med available in a liquid-containing capsule?

If yes, consider drawing the liquid out of the capsule in the pharmacy, prior to dispensing. Dispense the med in a properly labeled oral syringe to prevent inadvertent IV administration.

Is the dose or dosing interval different if using a different route or formulation?

If yes, make sure you change the dose or interval as appropriate. For example, if levothyroxine is switched from tablets to IV, the IV dose will need to be reduced to ~75% of the oral dose.¹²

Step 2: Consider the Type of Feeding Tube

Question

Considerations^1-6,8,9,17

Will the location of the tube affect the med’s efficacy?

Consider the type of tube:

Antacids, bismuth, and sucralfate (Carafate) need to go into the stomach because they act locally. These are NOT appropriate for feeding tubes that terminate in the intestine.

Quinolones are absorbed mainly in the duodenum. Tubes that terminate in the jejunum bypass the duodenum. Quinolones should NOT be administered through tubes that terminate in the jejunum.

Itraconazole and ketoconazole require an acidic environment for the best absorption. Bioavailability might be reduced if administered through tubes that terminate outside of the stomach.

To administer a PPI through tubes that terminate in the intestine, a prepared suspension of PPI dissolved in sodium bicarbonate is recommended. Sodium bicarbonate dissolves the enteric coating so the active drug can be absorbed in the intestine. Additionally, these suspensions may be less likely to clog feeding tubes.

Intrajejunal administration of drugs with extensive first-pass metabolism (e.g., beta-blockers, nitrates, opioids, tricyclics) can increase bioavailability.

Step 3: Other Considerations for Administration of Meds Through a Feeding Tube

Question

Considerations^1-6,8,9,17

Is the med likely to clog the tube?

Meds that are likely to clog an enteral tube include:

Dobhoff tubes are narrow, so only liquid meds (e.g., commercially available liquids, finely crushed tablets or capsule contents dissolved in water) should be used to prevent clogging.

Consider the size of the tube with some meds. For example, lansoprazole orally disintegrating tablets can be given via a size 8 French tube or larger, while the lansoprazole capsules require at least a size 16 French tube.⁸

Does the med interact with tube feeds?

Generally, do NOT mix meds with tube feedings, mix meds together, or give multiple meds at the same time.^5,13

Consider alternative meds, routes, or reduced dosing frequency (when possible) for meds that interact with tube feeds.²

Always flush tubes before AND after administration of a med with at least 15 mL to 30 mL of water (for adults).^2,5,8,13

Some drugs aren’t physically compatible with tube feeds. For example:

For meds that must be administered on an empty stomach, hold gastric feedings for 30 minutes before AND after drug administration. It’s not necessary to hold feedings if the feeding tube terminates in the intestine.

Phenytoin blood levels can be reduced by up to 75% with tube feeds. Can consider stopping tube feeds for two hours before AND after each dose.

Penicillin and tetracycline absorption can be reduced by tube feeds. Can consider stopping feeds one hour before AND two hours after administration of these drugs.

Regularly check levels if giving narrow therapeutic index meds (e.g., carbamazepine, digoxin) through feeding tubes.

Warfarin’s effectiveness can be reduced when given through a feeding tube. Monitor INR closely. Consider holding tube feeds for one hour before and one hour after administration.⁵

Tube feeds might reduce quinolone bioavailability. Stop tube feeds for at least one hour before AND two hours after quinolones are given. (Note that ciprofloxacin suspension may adhere to feeding tubes and cause occlusion.)

What to Recommend for Clogged Feeding Tubes

Clogging can be a major complication with feeding tubes. Inappropriate med administration and inadequate flushing can lead to clogging.

If a feeding tube is clogged, first try flushing it with warm water and gentle pressure using a large syringe (e.g., instill 5 mL of warm water and allow it to dwell for one minute, follow with a back-and-forth motion using a 30 to 60 mL catheter tip syringe [note that smaller syringes may create too much pressure, damaging the tube]).^6,11 Longer dwell times (e.g., ≤20 minutes), may be needed for stubborn clogs.¹³

Consider flushing with an alkalinized enzyme solution to unclog a tube occluded by drug residue. Here are some example protocols:^10-13

Avoid using juices, sodas, or meat tenderizer to unclog tubes.

Clog Zapper, a premixed enzyme kit, is more expensive than the pancreatic enzyme/sodium bicarbonate mixture, and no more effective.

Mechanical devices such as Bard Brush are typically meant for use with specific types of tubes and require special training.

Prevention is the best strategy. Flush tubes with 30 mL of water at least every eight hours.¹³