CHPPC Module 41, Section 4: NPO, Tube & Route Migration
MODULE 41: PHARMACY POLICIES, PROTOCOLS, & DOCUMENTATION

Section 4: NPO, Tube & Route Migration

Managing regimens for patients with feeding tubes or transitioning between PO, NPO, and IV routes: The Pharmacist as a Clinical Navigator.

SECTION 41.4

NPO, Tube & Route Migration

Ensuring therapeutic continuity when the path of medication administration changes.

41.4.1 The “Why”: The Clinical Navigator for Therapeutic Continuity

In the preceding sections, we have established the pharmacist’s role as the governor of substitutions and the architect of the MAR. We have focused on the what (therapeutic interchange), the when (scheduling semantics), and the what if (missed doses). This section addresses the critical questions of how and where. How do we deliver medications when the oral route, the superhighway of drug administration, is closed? Where in the GI tract will our drugs land, and how does that impact their effect? A patient’s journey through the hospital is rarely a straight line; it is a series of transitions. Patients are made NPO for procedures, they may require enteral feeding tubes for nutritional support, and they hopefully transition back to oral intake as they recover. Each of these transitions is a point of extreme vulnerability for medication safety and therapeutic continuity.

As a community pharmacist, you are a master of ensuring continuity in the outpatient world—managing refills, handling prior authorizations, and ensuring patients don’t run out of their essential medications. In the hospital, you apply this same core principle to a much more acute and rapidly changing environment. When a patient is made NPO or has a feeding tube placed, their entire medication regimen is at risk of being unintentionally discontinued or administered incorrectly. An order for “Hold all PO meds” is a clinical sledgehammer when surgical precision is needed. It is your job to step in as the clinical navigator, meticulously reviewing the patient’s regimen and charting a new course for each essential medication. You will prevent critical drugs from being held, ensure formulations are compatible with new access routes, and proactively manage the complex pharmacokinetic challenges that arise when the normal rules of oral administration no longer apply.

This is not a passive verification role. This is proactive, interventionist pharmacy at its most impactful. Your ability to manage these transitions directly prevents therapeutic gaps, avoids adverse drug events from improperly administered medications, and facilitates a smoother, safer patient journey. You will become the expert on the hospital floor for questions about crushing medications, drug-nutrient interactions, and the nuanced differences between gastric and jejunal administration. This mastery is a hallmark of an expert hospital pharmacist.

Retail Pharmacist Analogy: The Compounding Conundrum & The “Can This Be Crushed?” Hotline

Your entire career has prepared you for this role. You are already the local expert on medication formulations and administration, and you handle these complex scenarios every day.

1. Managing Tube Medications is like Non-Sterile Compounding: A pediatrician sends you a prescription for a blood pressure medication for a 2-year-old who obviously cannot swallow a tablet. There is no commercial liquid available. You don’t tell the parent it’s impossible. You become a compounder. You consult your references (like the extemporaneous formulation handbooks), you calculate the correct amount of crushed tablets, you select an appropriate vehicle (like Ora-Sweet), you ensure the stability of the final product, and you provide clear instructions for administration. This entire process—assessing the need, selecting a new formulation, ensuring stability and compatibility, and counseling on correct administration—is a direct parallel to managing medications for a patient with a feeding tube. You are simply applying your compounding mindset to a new delivery system.

2. Navigating Drug-Feed Interactions is like the “Take With Food vs. Empty Stomach” Hotline: You are the community’s go-to resource for administration instructions. A patient asks, “Can I take my iron pill with my morning coffee and milk?” You immediately step in: “No, the calcium in the milk will bind to the iron and prevent it from being absorbed. You need to take your iron at least an hour before or two hours after any dairy products.” Another patient asks about their new antibiotic. “Make sure to take this one with food to avoid stomach upset.” You are a master of drug-nutrient interactions. In the hospital, this expertise is elevated. The “food” is now a continuous, complex enteral nutrition formula. Your knowledge of chelation, binding, and pH-dependent absorption is now applied to prevent the feeding formula from inactivating critical medications like phenytoin or ciprofloxacin. You are performing the same core function—ensuring optimal drug absorption—just in a more controlled, and higher-stakes, environment.

41.4.2 A Pharmacist’s Guide to Enteral Access Devices

Before you can manage medications administered via enteral tubes, you must first understand the hardware. While there are many variations, enteral access devices are broadly categorized by their insertion site and where they terminate in the GI tract. As a pharmacist, you must be able to identify the type of tube a patient has, as it has profound implications for medication administration and absorption.

Masterclass Table: Types of Enteral Feeding Tubes
Tube Type & Abbreviation Diagram / Description Typical Use Key Pharmacist Considerations
Nasogastric (NG) Tube A thin, flexible tube inserted through the nares (nostril), down the esophagus, and into the stomach. Short-term use (<4-6 weeks) for nutritional support, medication administration, or gastric decompression (suction).
  • Risk of Misplacement: The tube can be inadvertently placed in the lungs, which would be catastrophic if medications were administered. Placement is always confirmed by x-ray.
  • Small Bore: Often narrow, making them prone to clogging. Meticulous flushing is essential.
  • Gastric Access: Medications are delivered to the stomach’s acidic environment. Standard oral drug administration rules generally apply.
Orogastric (OG) Tube Similar to an NG tube, but inserted through the mouth (oropharynx) and into the stomach. Used in patients who are intubated and sedated, where nasal passage irritation is a concern.
  • Functionally identical to an NG tube from a pharmacy perspective.
  • The patient is, by definition, unable to swallow, making this their only enteral access route.
Gastrostomy (G-tube) or Percutaneous Endoscopic Gastrostomy (PEG) Tube A tube placed surgically or endoscopically through the abdominal wall directly into the stomach. Long-term enteral access for patients with chronic conditions that impair swallowing (e.g., stroke, ALS, head/neck cancer).
  • Stable, Secure Access: Less prone to dislodgement than NG/OG tubes.
  • Larger Bore: Generally wider, reducing the risk of clogging.
  • Stomach Still in Play: Provides gastric access, so the acidic environment is available for drug dissolution.
Jejunostomy (J-tube) or Percutaneous Endoscopic Jejunostomy (PEJ) Tube A tube placed through the abdominal wall directly into the jejunum (the second part of the small intestine). Long-term feeding for patients who cannot tolerate gastric feeding due to issues like severe gastroparesis, gastric outlet obstruction, or high risk of aspiration.
  • CRITICAL: Bypasses the Stomach. This is the most important pharmacokinetic consideration. The acidic environment of the stomach is lost.
  • Drugs requiring acid for absorption will fail.
  • Modified-release dosage forms that rely on GI transit time will not work as intended.
  • This is considered “post-pyloric” access.
Gastrojejunostomy (G-J) Tube A combination tube with two ports. One port opens in the stomach (gastric port), and a longer, inner tube runs through it and opens in the jejunum (jejunal port). Used for patients who need gastric decompression (suction from the G port) but require simultaneous feeding into the small intestine (via the J port).
  • High Risk for Error: It is absolutely critical to know which port is for what. Medications intended for gastric absorption given down the J port may fail. Feedings given into the G port may be suctioned right back out.
  • Pharmacist’s Role: Always clarify which port to use for medications. The default is the gastric port unless there’s a specific reason not to use it.

41.4.3 The Rules of the Road: Masterclass on Tube Medication Administration

Safe and effective medication administration via an enteral tube is a science. It requires a systematic approach to formulation selection, preparation, and administration to ensure the patient receives the intended dose and the tube remains functional. As the pharmacist, you are the primary author of this plan.

The Hierarchy of Formulation Choice

When converting a solid oral dosage form for tube administration, there is a distinct hierarchy of preference, from most desirable to least desirable.

  1. Use FDA-Approved Commercial Liquid Formulation: This is always the gold standard. These products have proven stability, consistent concentration, and are designed for oral/enteral administration. Examples include levetiracetam solution, phenytoin suspension, and furosemide solution.
  2. Use Immediate-Release Tablets Crushed into a Slurry: If no liquid is available, the next best option is to crush an immediate-release tablet into a fine powder and mix it with 15-30 mL of sterile water. This is appropriate for the vast majority of non-modified-release medications.
  3. Use Contents of an Immediate-Release Capsule: The contents can be opened and mixed with water. However, some beads inside capsules are actually enteric-coated and should not be crushed (e.g., Proton Pump Inhibitors).
  4. Use Extemporaneously Compounded Oral Liquid: If no commercial liquid exists and crushing is not an option (e.g., the dose is too small to accurately obtain from a tablet), the pharmacy may need to compound a liquid from bulk powder. This is more common in pediatric settings. This is a last resort for adult floor stock needs due to stability and BUD concerns.
The Flushing Protocol: The Most Important Procedure

Tube occlusion is a serious and completely preventable complication. A clogged tube may need to be replaced, which can be an invasive and risky procedure. The single most important factor in preventing clogs is a meticulous flushing protocol. While this is a nursing function, you must understand it to educate and reinforce its importance.

The Step-by-Step Flushing Procedure:

  1. Confirm Tube Placement: Before any administration, the nurse must confirm the tube is in the correct position.
  2. Initial Flush: Flush the tube with at least 15-30 mL of sterile water. This clears the tube and ensures it is patent.
  3. Administer Med #1: Administer the first medication (in liquid form or as a properly prepared slurry).
  4. Intermediate Flush: Flush the tube with at least 5-15 mL of sterile water. This is CRITICAL. It clears the first medication completely before the second one is introduced, preventing physical and chemical incompatibilities within the tube itself.
  5. Administer Med #2: Administer the second medication.
  6. Repeat Flush: Flush again with 5-15 mL of sterile water. Repeat for all subsequent medications.
  7. Final Flush: After the last medication is given, perform a vigorous final flush with at least 30 mL of sterile water to ensure all medication is cleared from the tube and has reached the GI tract.

Pharmacokinetic Pitfalls in Tube Administration

Beyond the physical act of getting the drug down the tube, you must anticipate and manage the pharmacokinetic challenges that arise. This is where your clinical expertise adds immense value.

Masterclass Table: Drug-Enteral Feed Interactions
Drug Mechanism of Interaction Clinical Consequence Pharmacist’s Management Protocol
Phenytoin Binds to proteins and calcium salts in the enteral nutrition formula, forming an insoluble complex that is not absorbed. Dramatically reduced bioavailability (>70% reduction), leading to sub-therapeutic levels and breakthrough seizures. This is a non-negotiable HOLD. Stop the tube feedings for 1-2 hours before the phenytoin dose and for 1-2 hours after the dose. The tube must be flushed thoroughly before and after. Therapeutic drug monitoring is essential.
Fluoroquinolones (especially Ciprofloxacin) Chelation with divalent and trivalent cations (Ca2+, Mg2+, Fe3+) present in the feeding formula. Significant reduction in absorption, potentially leading to antibiotic treatment failure. HOLD required. Stop the tube feedings for at least 1 hour before and 2 hours after the ciprofloxacin dose. If possible, consider switching to an antibiotic that does not have this interaction (e.g., ceftriaxone).
Warfarin The enteral nutrition formula contains Vitamin K, the direct antagonist of warfarin. Warfarin resistance. The patient will require much higher doses to achieve a therapeutic INR. If the tube feeds are stopped suddenly, the Vitamin K source is removed, and the INR can shoot up to dangerously high levels. Consistency is Key. Do NOT hold the tube feeds. Instead, ensure the feeds are run at a consistent rate. Monitor the INR daily and anticipate that the patient’s warfarin dose will be higher while on feeds. Communicate clearly with the provider about the need for a dose increase, and more importantly, the need for a dose decrease if feeds are discontinued.
Levothyroxine Adsorption to the feeding tube itself and complexation with components of the feed. Poor and erratic absorption, leading to hypothyroidism. HOLD required. Stop the tube feedings for at least 1 hour before and 1 hour after the levothyroxine dose. Use of the oral solution may mitigate some of the binding issues but holding feeds is still recommended.
Carbamazepine Adheres to the plastic of the feeding tube and binds to the feeding formula. Erratic and significantly reduced absorption, risking breakthrough seizures. HOLD required. Stop tube feeds for 2 hours before and 2 hours after the dose. The suspension must be diluted with an equal volume of water before administration to reduce viscosity and binding. TDM is highly recommended.
The Osmolality Trap: Sorbitol and Diarrhea

Many commercial liquid medications (elixirs, syrups, solutions) use sorbitol as a sweetener and vehicle. Sorbitol is a potent osmotic agent. While a single small dose is harmless, administering multiple sorbitol-containing medications throughout the day via a feeding tube delivers a large osmotic load directly to the GI tract. This pulls water into the intestines, causing severe gas, cramping, and osmotic diarrhea.

The Pharmacist’s Role: When a tube-fed patient develops new-onset diarrhea, you must become a “sorbitol detective.” Review their medication list, specifically looking at the excipients in all the liquid formulations they are receiving. Common culprits include acetaminophen elixir, theophylline solution, and some liquid electrolyte replacements.

Action Plan:

  1. Identify the sorbitol-containing products.
  2. Look for sorbitol-free alternatives.
  3. If no alternative exists, recommend switching to a crushed tablet slurry of the same medication, which will not contain the sorbitol. This intervention can immediately resolve the patient’s diarrhea and is a high-impact pharmacy consultation.

41.4.4 Stomach vs. Jejunum: The Post-Pyloric Frontier

For most of your career, you have relied on a fundamental pharmacokinetic assumption: oral drugs start in the stomach. The highly acidic environment of the stomach (pH 1.5-3.5) begins the process of disintegration and dissolution before the drug passes through the pyloric sphincter into the small intestine for absorption. Administration of medications through a jejunostomy tube (J-tube) shatters this assumption. By delivering the drug directly into the alkaline environment of the jejunum (pH 6-7), you are stepping into a different pharmacokinetic world. Understanding the consequences of bypassing the stomach is an advanced skill that distinguishes a proficient pharmacist from an expert one.

Key Pharmacokinetic Principles Altered by J-Tube Administration
  • Loss of Acidic Environment: Drugs that are weak bases are formulated as salts (e.g., hydrochloride salts) that dissolve more readily in the acidic stomach. More importantly, certain drugs absolutely require an acidic pH to be absorbed. Giving these via a J-tube can lead to near-complete treatment failure.
  • Altered Dissolution Time: Drugs have less time to dissolve before reaching their primary absorption sites. A solid dosage form that would normally spend an hour in the stomach now arrives in the jejunum as a chunk of powder, which may or may not dissolve quickly enough in the alkaline environment.
  • Premature Activation: Enteric coatings are designed to protect acid-labile drugs from the stomach. In the J-tube, the drug is released directly into the alkaline environment it was designed for, but this can sometimes be problematic if the drug itself is unstable or if it was meant to be released more distally.
Masterclass Table: J-Tube Administration – Problematic Drugs & Solutions
Drug / Class The Problem with J-Tube Administration Clinical Consequence Pharmacist’s Action Plan
Azole Antifungals (Itraconazole, Ketoconazole) These drugs are weak bases that are practically insoluble at neutral pH. They absolutely require an acidic environment to be ionized and absorbed. Complete therapeutic failure. The drug will pass through the GI tract unabsorbed. Oral route is not viable via J-tube. This is a hard stop. Contact the provider immediately. The patient must be switched to an alternative agent that does not have this pH-dependent absorption, such as IV amphotericin B or an echinocandin, or possibly an azole with better bioavailability like voriconazole or posaconazole (if appropriate for the indication).
Iron Supplements (e.g., Ferrous Sulfate) Iron is best absorbed in its ferrous (Fe2+) state, which is favored in the acidic environment of the stomach. In the alkaline jejunum, it is rapidly oxidized to the less soluble ferric (Fe3+) state. Significantly reduced iron absorption, making oral replacement therapy ineffective. Switch to a liquid formulation (e.g., ferrous sulfate elixir) if available. Administering with an acidic substance like ascorbic acid (Vitamin C) can help, but absorption will still be poor. For severe deficiency, the patient will likely require IV iron replacement (e.g., iron sucrose, ferumoxytol).
Proton Pump Inhibitors (PPIs) PPIs are acid-labile prodrugs. The enteric-coated granules are designed to protect the drug from stomach acid. When given via J-tube, they are released into an alkaline environment, become activated, and are then destroyed by the alkalinity before they can be absorbed to work systemically. Complete therapeutic failure. This is a major clinical challenge. Standard capsules/granules are ineffective. You have two primary options:
  1. Recommend switching to a continuous IV PPI infusion (e.g., pantoprazole 8 mg/hr).
  2. If the team insists on enteral, you must use a formulation that can bypass this issue. This may involve compounding an immediate-release suspension with sodium bicarbonate to protect the drug. This is complex and requires a specific protocol.
Ciprofloxacin Suspension The commercial suspension is oil-based and very thick. It is not designed for post-pyloric administration and can clump and clog the tube. Tube occlusion and erratic dosing. Do not use the suspension. The preferred method is to use crushed immediate-release ciprofloxacin tablets mixed into a water slurry. Remember to still hold the tube feeds due to the chelation interaction.

41.4.5 The Full Circle: Proactive Regimen Navigation

Managing a patient’s regimen through these transitions is one of the most cognitively demanding and clinically valuable things a pharmacist can do. It requires foresight, meticulous planning, and clear communication. You are not just reacting to problems; you are anticipating them and creating a seamless therapeutic plan that adapts with the patient. Let’s walk through a common clinical scenario.

Case Study: Mr. Miller’s Journey

Mr. Miller is a 72-year-old male with a history of hypertension, a seizure disorder, and GERD who is admitted for a stroke. He fails his swallow evaluation and is initially made NPO, and a PEG tube is planned for long-term support.

Home Medication List:

  • Lisinopril 40 mg PO Daily
  • Metoprolol Succinate (Toprol XL) 100 mg PO Daily
  • Levetiracetam (Keppra) XR 1000 mg PO Q12H
  • Pantoprazole DR 40 mg PO Daily

Phase 1: Admission & NPO Status (Days 1-2)

The admitting physician places an order for “NPO, IV fluids. Resume home meds.” This is your first call to action.

Pharmacist’s NPO Triage & Intervention Plan
  • Lisinopril: (Category 3: Needs Clarification) Patient’s blood pressure is currently stable. It is safe to hold an ACE-inhibitor for a short period, especially in a stroke patient where permissive hypertension may be desired. Action: Recommend to provider: “Hold lisinopril while patient is NPO and hemodynamics are being closely monitored.”
  • Metoprolol Succinate XL: (Category 2: Must Be Given) Abruptly stopping a beta-blocker is dangerous. The XL formulation cannot be given IV. Action: Proactively contact provider: “To prevent rebound tachycardia, recommend switching Metoprolol Succinate XL 100 mg daily to an equivalent IV dose. A reasonable start is Metoprolol Tartrate 5 mg IV Q6H. I will enter this order for your approval.”
  • Levetiracetam XR: (Category 2: Must Be Given) Stopping an AED is non-negotiable. The XR form cannot be given IV. Action: Proactively contact provider: “To maintain seizure prophylaxis, recommend switching Levetiracetam XR 1000 mg Q12H to the equivalent IV dose of Levetiracetam 1000 mg IV Q12H.”
  • Pantoprazole DR: (Category 1: Safe to Hold, but…) While it’s safe to hold for a day, the patient has GERD, and NPO status can be stressful. An IV formulation is readily available. Action: Proactively contact provider: “Recommend switching PO pantoprazole to Pantoprazole 40 mg IV Daily for acid suppression while NPO.”

Phase 2: PEG Tube Placement & Enteral Regimen (Days 3-7)

Mr. Miller’s PEG tube is successfully placed and tube feeds are initiated. It is now your job to migrate his IV regimen to an enteral-friendly one.

Pharmacist’s Enteral Migration Plan
  • Lisinopril: Patient’s BP is now a target for control. Action: Discontinue the hold. Order Lisinopril 40 mg via PEG tube daily. This is an immediate-release tablet that can be safely crushed.
  • Metoprolol: The patient is no longer NPO. IV access should be de-escalated. Action: Discontinue IV metoprolol. The long-acting succinate salt cannot be crushed. You must use the immediate-release tartrate salt. To match the 24-hour coverage, convert the total daily IV dose (20 mg) to a PO equivalent (IV:PO ratio ~1:2.5 -> 50 mg/day) and schedule it throughout the day. Order Metoprolol Tartrate 25 mg via PEG tube Q12H.
  • Levetiracetam: IV route is no longer necessary. Action: Discontinue IV levetiracetam. The XR formulation cannot be crushed. Switch to the immediate-release equivalent. Order Levetiracetam 1000 mg via PEG tube Q12H. (Note: Levetiracetam IR is given Q12H, so this is a simple formulation switch).
  • Pantoprazole: IV route no longer necessary. Action: Discontinue IV pantoprazole. The DR capsule’s granules must be handled correctly. Order Pantoprazole DR 40 mg via PEG tube daily. Add a nursing communication: “Open capsule, mix intact granules with 10 mL of apple juice, and administer via PEG tube. Do not crush granules. Flush tube well.”

Phase 3: Transition to Oral Diet & Discharge Planning (Days 8+)

Mr. Miller’s swallow function improves, and he begins to tolerate an oral diet. Your final task is to simplify his regimen and convert it back to one that is safe and manageable for discharge.

Pharmacist’s Oral Migration & Discharge Plan
  • Lisinopril: No change needed. Action: Continue Lisinopril 40 mg PO Daily.
  • Metoprolol: The Q12H crushed regimen is complex for a patient at home. Action: Convert back to the simpler, home regimen. Discontinue Metoprolol Tartrate 25 mg Q12H. Order Metoprolol Succinate XL 100 mg PO Daily.
  • Levetiracetam: The Q12H IR regimen is acceptable, but the patient was on the XR version at home for convenience. Action: Convert back to the home regimen. Discontinue Levetiracetam IR 1000 mg Q12H. Order Levetiracetam XR 1000 mg PO Q12H.
  • Pantoprazole: No change needed. Action: Continue Pantoprazole DR 40 mg PO Daily.

By the end of this journey, you have navigated Mr. Miller’s regimen through three distinct phases, ensuring he never missed a critical dose, received medications via the correct route and formulation at all times, and is being discharged on the exact regimen he is familiar with. This is the epitome of the pharmacist’s role as a clinical navigator.