A stomach pump is a medical procedure, formally called gastric lavage, that empties the stomach by flushing it with fluid. It’s most commonly associated with poisoning or drug overdose, though it’s used far less often today than most people assume. The procedure involves inserting a large tube through the mouth into the stomach, then cycling water or saline in and out until the stomach contents are removed.
How the Procedure Works
The process starts with a large, flexible tube inserted through the mouth and guided down the esophagus into the stomach. The tube is wide enough to allow solid material, like partially dissolved pills, to pass through. Before insertion, the medical team measures the tube against the outside of your body, from the mouth down to the stomach area, to estimate the correct depth. A lubricant is applied to make passage easier.
Once the tube is confirmed to be in the stomach (typically by injecting a small puff of air through the tube and listening with a stethoscope over the abdomen), the lavage cycles begin. For adults, about 200 to 300 milliliters of fluid, roughly a cup or so, is poured into the stomach through the tube. The fluid mixes with whatever is in the stomach, and then drains back out by gravity or gentle suction. This cycle repeats until the fluid coming back out runs clear, which typically takes two to five rounds. In some cases, flushing continues well beyond that point.
You’re positioned on your left side during the procedure, with your head tilted slightly downward. This position keeps the stomach’s natural exit point (the pylorus, which leads to the intestines) elevated, helping trap contents in the stomach rather than pushing them further into the digestive tract. It also reduces the risk of fluid entering the lungs.
When It’s Used
Gastric lavage is reserved for serious, potentially life-threatening poisonings, and even then, major toxicology organizations recommend against using it routinely. A joint position statement from the American Academy of Clinical Toxicology and the European Association of Poisons Centres and Clinical Toxicologists states that the procedure should only be considered when someone has ingested a potentially lethal amount of poison and the procedure can be performed within 60 minutes of ingestion.
That one-hour window is critical. After about an hour, much of what’s in the stomach has already moved into the small intestine, where lavage can’t reach it. A controlled study using acetaminophen found that gastric lavage performed at the one-hour mark reduced absorption by only about 20% on average. The longer the delay, the less effective the procedure becomes.
In practice, most poisoning cases are now managed with other approaches, such as activated charcoal (which binds to toxins in the stomach) or specific antidotes. Stomach pumping has become relatively uncommon in emergency departments because the risks often outweigh the modest benefit, especially when treatment is delayed.
When It’s Too Dangerous
There are several situations where gastric lavage is strictly off-limits. If someone has swallowed a corrosive substance, like drain cleaner or strong acids, the procedure would force that substance back up through the esophagus a second time, causing additional burns and tissue damage. Similarly, if someone swallowed a petroleum-based product or other hydrocarbon, the greatest danger is the substance getting into the lungs, and lavage increases that risk.
The procedure is also contraindicated in anyone who has lost the ability to protect their own airway, meaning they can’t cough or swallow reflexively. Without that protection, fluid or stomach contents can easily be inhaled into the lungs. If lavage is deemed necessary in an unconscious patient, a breathing tube is placed first to seal off the airway.
Risks and Complications
The most serious risk is aspiration, which means stomach contents or lavage fluid enter the lungs. This can cause a range of problems from mild inflammation to full-blown respiratory failure. About a third of patients who develop significant lung inflammation from aspiration go on to develop acute respiratory distress syndrome, a severe condition that carries roughly a 30% mortality rate. While this extreme outcome is uncommon, even minor aspiration can cause coughing, wheezing, shortness of breath, and low oxygen levels.
Other potential complications include injury to the esophagus or throat from the tube itself, gagging and vomiting during insertion, and in rare cases, perforation of the esophagus or stomach. The procedure can also inadvertently push some stomach contents past the pylorus and deeper into the intestines, potentially increasing absorption of the very substance doctors are trying to remove.
What the Experience Feels Like
Stomach pumping is not a comfortable procedure. The tube used is significantly larger than a standard feeding tube, because it needs to be wide enough to retrieve solid material. Insertion triggers a strong gag reflex in most people, and the repeated filling and draining of the stomach can cause nausea and cramping. Patients are sometimes sedated beforehand, particularly if they’re agitated or unable to cooperate, though full general anesthesia is not standard.
The entire process can take anywhere from 20 minutes to over an hour depending on how many lavage cycles are needed and what was ingested. Afterward, the throat is often sore from the tube, and some people experience hoarseness or difficulty swallowing for a day or two. In an emergency setting, the lavage is typically just one part of a larger treatment plan that may include IV fluids, monitoring, and administration of specific antidotes or activated charcoal through the same tube before it’s removed.