A nasogastric (NG) tube is a flexible plastic tube inserted through the nose and down into the stomach. Its main jobs are draining the stomach when something is blocking or slowing digestion, delivering liquid nutrition to people who can’t eat by mouth, and occasionally removing toxic substances after a poisoning. The specific purpose depends on why a patient needs one, but the tube itself is simple: it creates a direct pathway between the outside world and the stomach.
Draining the Stomach (Decompression)
The most common hospital use of an NG tube is decompression, which means removing air, fluid, and digestive secretions that have built up in the stomach. This is critical when a bowel obstruction prevents the normal downward flow of digested food. Without drainage, pressure builds, causing severe nausea, vomiting, bloating, and risk of aspiration (inhaling stomach contents into the lungs).
Decompression tubes have two channels inside them. The larger channel connects to gentle wall suction and pulls fluid out. The smaller channel lets air flow in so the suction doesn’t cause the tube to stick to the stomach lining or collapse against it once the stomach empties. You can think of it like the second hole on a straw lid: it prevents a vacuum seal. Decompression is also routine after certain abdominal surgeries to keep the stomach empty while the gut wakes back up from anesthesia.
Delivering Nutrition
When someone can’t chew, swallow safely, or eat enough to meet their calorie needs, a smaller, thinner NG tube can deliver liquid formula directly to the stomach. This is called enteral feeding. It’s used for people recovering from strokes, head and neck surgeries, severe illness in the ICU, or conditions that make swallowing dangerous.
Feedings can be given as scheduled boluses (a set volume pushed through the tube several times a day) or as a slow, continuous drip from a pump. A typical formula provides about 1 calorie per milliliter, so someone receiving 750 to 1,000 milliliters per day gets 750 to 1,000 calories. Medications can also be crushed or dissolved and given through the tube.
European nutrition guidelines recommend NG tube feeding for a maximum of four to six weeks. If someone needs tube feeding longer than that, a more permanent tube placed directly through the abdominal wall into the stomach (a gastrostomy tube) is generally preferred, since it’s more comfortable for long-term use and carries fewer nasal and throat complications.
Removing Toxins (Gastric Lavage)
In rare poisoning cases, a large-bore NG tube can be used to wash out the stomach, a procedure called gastric lavage. Water or saline is flushed in and then drained out repeatedly to remove as much of the ingested substance as possible. This is only considered when someone has very recently swallowed a potentially fatal dose of a toxic substance, and even then, the risks are weighed carefully against limited evidence that the procedure improves outcomes. It’s far less common today than it was decades ago, and most emergency departments reserve it for very specific, time-sensitive situations.
What Insertion Feels Like
The tube passes through one nostril, along the floor of the nasal passage, down the back of the throat, through the esophagus, and into the stomach. The most uncomfortable moment for most people is when the tube reaches the back of the throat, triggering a gag reflex. A nurse will typically ask you to tuck your chin toward your chest and take small sips of water through a straw to help the tube slide past this point. The whole process usually takes only a few minutes, though it can feel longer. Some hospitals offer a numbing spray or gel for the nostril and throat beforehand.
Because it can be an uncomfortable and somewhat private experience, nurses will often ask whether you’d like visitors to step out of the room during insertion.
Confirming Correct Placement
Once the tube is in, the medical team needs to verify it actually reached the stomach and didn’t accidentally curl into the airway or stop short in the esophagus. The gold standard is a chest X-ray showing the full length of the tube, with the tip sitting in the mid-stomach area. A quicker first-line check involves drawing a small sample of fluid from the tube and testing its pH: a strongly acidic reading suggests stomach placement. However, certain medications like antacids or acid-reducing drugs can throw off this test, making an X-ray necessary.
After confirmed placement, the nurse marks the tube where it exits the nose. This reference point helps detect if the tube shifts later. Patients who are confused or have altered consciousness get extra monitoring, since they’re at higher risk for the tube moving without anyone noticing.
Daily Care and Maintenance
An NG tube can clog, especially when thick formulas or crushed medications pass through it. To keep it clear, nurses flush the tube with about 30 milliliters of water using a large syringe. Flushing happens at least once per nursing shift, immediately before and after each feeding, and before and after every medication dose. During continuous feedings, flushes occur at regular scheduled intervals throughout the day. Tap water is the standard flushing fluid in most settings, though sterile water may be used for patients with compromised immune systems.
The skin around the nostril where the tube sits also needs regular cleaning and monitoring. Tape or a securing device holds the tube in place and gets changed when it loosens or gets damp. Keeping the nostrils clean and moisturized helps prevent irritation and skin breakdown, which can become a real source of discomfort over days or weeks.
Common Side Effects
NG tubes are generally safe, but they’re not comfortable. A sore throat, irritation inside the nostril, and a persistent urge to swallow or gag are the most frequent complaints. Some people develop minor nosebleeds from the tube rubbing against nasal tissue. Sinus pressure and earaches can also occur because the tube partially blocks normal drainage pathways in the nose.
The most serious risk is aspiration, where stomach contents travel up alongside or around the tube and enter the lungs, potentially causing pneumonia. Keeping the head of the bed elevated during feeding significantly reduces this risk. Tube displacement is another concern: if the tube migrates out of position, formula or medications could be delivered to the wrong place. That’s why regular position checks and monitoring are part of standard care for anyone with an NG tube in place.