Gastric Outlet Obstruction

Overview

Gastric outlet obstruction is a blockage where the stomach narrows and empties into the first part of the small intestine (the duodenum). When this passage is blocked or severely narrowed, food and stomach contents cannot move forward, so they back up in the stomach. The result is vomiting, a feeling of fullness, and difficulty keeping food down.

The obstruction can be partial or complete and may develop gradually or more suddenly. It is not a single disease but a complication of several underlying conditions, ranging from long-standing ulcers to tumors. Treatment depends on finding and addressing the cause.

Because the stomach cannot empty, food and fluids accumulate, which is why vomiting is the most prominent symptom and why people often feel full after eating very little. Over time, repeated vomiting can lead to dehydration, weight loss, and imbalances in the body's salts and acids. Identifying whether the blockage comes from a treatable cause like an ulcer or from a tumor is the key first step in care.

Symptoms

Typical symptoms include:

• Vomiting, often of undigested food eaten hours earlier
• A feeling of fullness or bloating after eating only a small amount
• Upper abdominal pain or discomfort
• Nausea and belching
• Loss of appetite and unintended weight loss
• Dehydration if vomiting is persistent

Frequent vomiting can lead to dehydration and chemical imbalances in the blood, which may need urgent treatment.

Causes

Several conditions can block the stomach outlet:

• Peptic ulcer disease: Long-standing ulcers near the outlet can cause scarring and swelling that narrow the passage.
• Tumors: Cancers of the stomach or pancreas, or other masses, can press on or invade the outlet.
• Inflammation and scarring: Chronic inflammation, prior surgery, or swallowed caustic substances can cause strictures.
• Pyloric stenosis: In infants, thickening of the outlet muscle causes obstruction.

Risk Factors

• A history of peptic ulcers or H. pylori infection
• Long-term use of NSAID painkillers
• Stomach or pancreatic cancer
• Previous abdominal surgery
• Chronic inflammation of the stomach or duodenum

In adults, the balance of causes has shifted over the years. Effective ulcer treatments have made ulcer-related obstruction less common, so tumors now account for a larger share of cases, which is why evaluation always includes looking carefully for a growth.

Diagnosis

Doctors diagnose gastric outlet obstruction by confirming the blockage and finding its cause:

• Upper endoscopy: A camera passed through the mouth views the stomach outlet directly and allows biopsies to check for ulcers or tumors.
• CT scan: Shows the stomach, the level of blockage, and surrounding structures.
• Upper GI series: X-rays after drinking contrast can show delayed emptying.
• Blood tests: Check for dehydration and chemical imbalances caused by vomiting.

Treatment

Treatment first stabilizes the person and then addresses the underlying cause:

• Initial care: Intravenous fluids, correction of chemical imbalances, and a tube to empty the stomach.
• Treating ulcers: Acid-reducing medicines and treatment of H. pylori, which can relieve obstruction caused by swelling.
• Endoscopic treatment: Balloon dilation can widen a narrowed outlet, or a stent can hold it open in some cases.
• Surgery: Used to bypass or remove the blockage, especially when caused by scarring or a tumor.
• Cancer treatment: If a tumor is the cause, care is directed at the underlying cancer.

The right treatment depends heavily on the cause and the person's overall health. Obstruction from a peptic ulcer may resolve with medical therapy alone, while obstruction from a tumor often needs a procedure to restore the ability to eat, whether a stent, a surgical bypass, or removal of the blockage. Nutrition support is an important part of care while the obstruction is being treated.

Prevention

• Treat peptic ulcers promptly and get tested for H. pylori if you have ulcer symptoms
• Use NSAID painkillers only as needed and with stomach protection if long-term
• Avoid smoking, which slows ulcer healing
• Seek evaluation for persistent vomiting or unexplained weight loss

When to See a Doctor

See a doctor if you have repeated vomiting, especially of old or undigested food, ongoing fullness after small meals, or unexplained weight loss. Seek emergency care for persistent vomiting with signs of dehydration, severe abdominal pain, vomiting blood, or black, tarry stools, which can indicate a serious complication.

Related Topics

Frequently Asked Questions

References

1. National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Digestive Diseases.
2. Mayo Clinic. Peptic ulcer — Complications.
3. MedlinePlus, U.S. National Library of Medicine. Gastric outlet obstruction.
4. American College of Gastroenterology. Gastric and Duodenal Disorders.