Gastric lavage, commonly called stomach pumping, is a medical procedure that flushes out the contents of your stomach through a tube. It’s used primarily in poisoning or overdose emergencies to remove a toxic substance before your body absorbs it. Once a routine part of emergency care, it’s now reserved for specific, serious situations where other treatments aren’t sufficient.
How the Procedure Works
A healthcare provider passes a large tube through your mouth or nose and down into your stomach. Before starting, they position you on your left side with your head tilted slightly lower than your chest. This position keeps stomach contents from moving into the intestines and reduces the risk of fluid entering your lungs.
Once the tube is in place, the provider flushes a small amount of fluid (warm water or saline) into your stomach, waits a minute or two, then drains everything back out. For adults, each flush uses up to 300 mL of fluid. For children, it’s about 10 mL per cycle. The process repeats until the fluid coming back runs clear, or until about two to three liters of solution have been used. The drained fluid carries out whatever was in the stomach, including the toxic substance.
When It’s Used
Gastric lavage is considered when someone has swallowed a dangerous substance within the past one to two hours, and the amount ingested is likely to cause serious harm if it stays in the body. The one-hour window matters because after that point, most substances have already moved out of the stomach and into the intestines, where lavage can’t reach them. Some drugs slow stomach emptying, which can extend that window slightly.
The procedure gets stronger consideration in two scenarios: when the poison doesn’t have an effective antidote (certain herbicides, for example), or when the best available treatment would take too long to arrange. In everyday poisoning cases, it’s rarely the first choice.
Why It’s No Longer Routine
For decades, stomach pumping was a standard response to poisoning. That changed after major toxicology organizations reviewed the evidence and found that the procedure’s benefits were modest and unreliable, while its risks were real. One study testing lavage on a common painkiller found that even at exactly one hour after ingestion, the reduction in drug absorption was too small to be clinically meaningful.
The current standard in most poisoning cases is activated charcoal, a substance that binds to toxins in the stomach and prevents absorption. It’s simpler, safer, and effective against a wide range of poisons. Gastric lavage is now generally reserved for extremely serious poisonings, particularly when the toxin doesn’t bind well to activated charcoal or when the quantity swallowed is too large for charcoal alone to handle.
Risks and Complications
Gastric lavage is not a gentle procedure, and it carries meaningful risks. The most dangerous complications are aspiration (fluid or stomach contents entering the lungs), aspiration pneumonia, and perforation of the esophagus or stomach. In one study of pesticide-poisoned patients, aspiration pneumonia occurred in anywhere from 2% to 13% of cases depending on the hospital. Another study found that combining lavage with activated charcoal raised the rate of aspiration pneumonia to 8.5%, compared to 0% when charcoal was used alone.
Other complications include drops in blood oxygen levels (seen in about 13% of patients in one observational study), spasm of the airway, electrolyte imbalances, and the tube becoming stuck in the throat. Serious cardiac events have also been documented during the procedure. These risks are a major reason the procedure has fallen out of routine use.
Situations Where It Should Not Be Done
Gastric lavage is off the table in certain situations. If someone has swallowed a corrosive substance like a strong acid or alkali, passing a tube risks perforating tissue that’s already been chemically burned. It’s also contraindicated after swallowing certain petroleum-based liquids (hydrocarbons) because of the high risk of the substance entering the lungs during the procedure. If a person is unconscious or has lost their gag reflex, lavage can only proceed if a breathing tube is placed first to protect the airway.
What the Experience Feels Like
If you’re conscious during gastric lavage, the experience is uncomfortable. The tube passing through the throat triggers gagging, and the repeated filling and draining of the stomach can cause nausea and cramping. In some emergency situations, patients are sedated or have a breathing tube placed under general anesthesia before the procedure begins, which eliminates the discomfort but adds its own risks. The entire process typically takes 20 to 30 minutes, though this varies depending on how quickly the fluid runs clear.
After the procedure, your throat may feel sore for a day or two from the tube. Providers will monitor you for signs of complications, particularly breathing problems that could indicate aspiration. In poisoning cases, additional treatments like activated charcoal or specific antidotes often follow the lavage.