A burning sensation in your stomach is most often caused by excess acid irritating the stomach lining, a condition broadly called gastritis. But several different problems can create that same burning feeling, ranging from common triggers like spicy food and painkillers to bacterial infections and acid reflux. Understanding the specific pattern of your symptoms can help narrow down what’s going on.
Gastritis: The Most Common Cause
Gastritis is inflammation of the stomach lining, and it’s the most straightforward explanation for a burning feeling in your upper abdomen. Most people with mild gastritis don’t have symptoms at all, but when they do, the hallmarks include a gnawing or burning pain in the area just below your ribs, nausea, feeling full unusually fast during meals, and sometimes vomiting.
The stomach lining normally protects itself from its own acid by producing a thick layer of mucus and chemical messengers called prostaglandins that regulate blood flow and mucus production. When something disrupts that protective barrier, acid comes into direct contact with the tissue underneath, creating that characteristic burn. This disruption can happen acutely, like after a night of heavy drinking, or build slowly over months from chronic infection or regular painkiller use.
H. pylori Infection
One of the most common causes of chronic gastritis worldwide is a bacterium called H. pylori, which burrows into the stomach lining and triggers ongoing inflammation. Roughly 36% of people in the United States carry H. pylori, and globally the number is even higher: about 60% of the world’s population is infected. Rates vary widely by region, from around 19% in Switzerland to 88% in Nigeria.
Most people with H. pylori never develop symptoms, but in those who do, the infection can cause a persistent burning or aching in the stomach, bloating, nausea, and in some cases ulcers. The infection is usually picked up in childhood and can last a lifetime if untreated. Testing is straightforward. A breath test, where you drink a solution and then breathe into a collection bag, has a sensitivity of 90 to 96% and a specificity of 88 to 98%, making it one of the most reliable non-invasive options. Stool tests using an immune-based method have similar accuracy. If H. pylori is confirmed, a course of antibiotics combined with an acid-reducing medication typically clears the infection.
Painkillers and NSAIDs
Over-the-counter anti-inflammatory drugs like ibuprofen, naproxen, and aspirin are a major cause of stomach burning, especially with regular use. These medications work by blocking an enzyme that drives inflammation, but that same enzyme also maintains the stomach’s protective lining. When the drug shuts it down, mucus production drops, blood flow to the stomach wall decreases, and the tissue becomes far more vulnerable to acid damage.
This is why some people notice stomach discomfort within days of starting a daily painkiller regimen, and why long-term use can progress from simple irritation to a full stomach ulcer. Taking these medications with food helps somewhat, but it doesn’t eliminate the risk. If you rely on NSAIDs regularly for pain and notice a burning stomach, that connection is worth exploring with your doctor.
Acid Reflux and GERD
Acid reflux happens when stomach acid flows backward into the esophagus, and it can sometimes produce a burning sensation that feels like it’s in the stomach but actually originates higher up. The classic symptom of GERD (gastroesophageal reflux disease) is a burning feeling that rises from the middle of the chest toward the throat, often with a sour or acidic taste in the mouth. Other signs include chronic coughing, hoarseness, and pain or difficulty swallowing.
A ring of muscle at the bottom of the esophagus normally acts as a one-way valve, keeping acid in the stomach. Certain things weaken this valve. High-fat meals, alcohol, chocolate, and carbonated drinks can all reduce the pressure that keeps it closed, allowing acid to splash upward. Excess body weight and diabetes are also established risk factors. If your burning gets worse after meals, when lying down, or when bending over, reflux is a likely contributor.
Stomach Ulcers
When gastritis or H. pylori infection goes untreated long enough, the damage to the stomach lining can deepen into an open sore called an ulcer. Ulcers produce a more intense, localized burning that often has a predictable rhythm. Many people notice the pain is worst on an empty stomach or in the middle of the night, and temporarily improves after eating because food buffers the acid. The burning can last minutes to hours and may come and go over weeks.
Ulcers caused by NSAIDs and those caused by H. pylori account for the vast majority of cases. Both are treatable, but ulcers that go ignored can bleed or, rarely, perforate the stomach wall entirely.
Functional Dyspepsia
Sometimes the stomach burns and all the tests come back normal. No ulcer, no infection, no visible inflammation. This is called functional dyspepsia, and it’s diagnosed when you have persistent symptoms like burning in the upper abdomen, pain below the ribs, uncomfortable fullness after eating, or feeling full too quickly, but an endoscopy and other workups find no structural explanation.
Functional dyspepsia is thought to involve heightened sensitivity in the nerves of the stomach, abnormal motility (the stomach not emptying at its usual pace), or a combination of both. It’s a real condition, not a dismissal. It affects a significant percentage of people with chronic stomach complaints, and treatments typically focus on low-dose acid suppression, dietary adjustments, and sometimes medications that address nerve sensitivity.
Food and Lifestyle Triggers
Even without an underlying disease, certain foods and habits can provoke stomach burning on their own. Alcohol irritates the stomach lining directly. Coffee and caffeine increase acid production. Spicy foods containing capsaicin can trigger a burning sensation in people with a sensitive stomach, though they don’t cause actual tissue damage in most cases.
Eating large meals, eating late at night, and lying down soon after eating all increase the likelihood of acid-related discomfort. Smoking weakens the valve between the stomach and esophagus and also reduces blood flow to the stomach lining, making it less resilient. For many people, identifying and reducing one or two key triggers produces noticeable relief within a week or two.
How Acid-Reducing Medications Work
The most effective medications for stomach burning are proton pump inhibitors, commonly known as PPIs (like omeprazole). These drugs shut down the acid-producing pumps in the stomach lining by binding to them permanently. Because the binding is irreversible, a single dose suppresses acid production for about 48 hours, even though the drug itself leaves your bloodstream within an hour or two. It takes about two to three days of daily use to reach the full level of acid suppression.
Over-the-counter antacids neutralize acid that’s already been produced and work within minutes, but their effects are short-lived. H2 blockers (like famotidine) reduce acid production through a different mechanism and fall somewhere in between: faster onset than PPIs but less powerful overall. For most causes of stomach burning, a short course of acid suppression combined with removing the underlying trigger is the standard approach.
When Stomach Burning Needs Urgent Attention
Most stomach burning is uncomfortable but not dangerous. However, certain signs suggest something more serious. If you’re vomiting blood, notice blood in your stool, or your stools appear black and tarry, seek medical attention right away. These are signs of bleeding in the digestive tract, possibly from an ulcer. Unintentional weight loss, difficulty swallowing, and persistent vomiting also warrant prompt evaluation.
In rare cases, a tumor called a gastrinoma can cause the stomach to massively overproduce acid, leading to severe ulcers and burning. This condition, known as Zollinger-Ellison syndrome, is uncommon but is suspected when ulcers keep recurring despite treatment or appear in unusual locations. Blood tests showing very high levels of the hormone gastrin, particularly above 1,000 pg/mL alongside highly acidic stomach contents, point to this diagnosis.