Stomach pain has dozens of possible causes, ranging from something as simple as trapped gas to conditions that need medical attention. Most of the time, the culprit is temporary: something you ate, stress, or a mild infection. But because so many organs are packed into your abdomen, the location, timing, and type of pain all offer clues about what’s actually going on.
Where It Hurts Matters
Your abdomen isn’t one uniform space. It contains your stomach, liver, gallbladder, pancreas, intestines, and (if you have them) reproductive organs. Pain in different areas often points to different sources.
- Upper right: Pain here, especially after eating fatty foods, often involves the gallbladder. Gallstones or gallbladder inflammation are the most common culprits. Liver problems, including hepatitis, can also cause pain in this area.
- Upper left or center: This is where your actual stomach sits. Gastritis, stomach ulcers, and acid reflux tend to produce burning or gnawing pain here. Splenic problems, though less common, also cause upper-left pain.
- Lower right: Sharp pain that starts near your belly button and migrates to the lower right, especially with nausea and loss of appetite, is a classic pattern for appendicitis.
- Lower left: In adults over 40, pain here is commonly caused by diverticulitis, an inflammation of small pouches that form in the colon wall.
- All over or hard to pinpoint: Generalized pain often comes from gas, a stomach virus, food intolerance, or stress.
The Most Common Everyday Causes
If your stomach hurts and you’re otherwise healthy, the explanation is usually one of a handful of things. Gas and bloating top the list. When bacteria in your large intestine ferment carbohydrates your small intestine didn’t fully absorb, they produce gas that stretches the intestinal walls and causes cramping. Certain foods are particularly prone to this: onions, garlic, beans, wheat, dairy (if you’re lactose intolerant), and artificial sweeteners like sorbitol. These belong to a group of short-chain carbohydrates that the small intestine absorbs poorly, and they’re the basis of the low-FODMAP diet that many people with chronic bloating find helpful.
Constipation is another surprisingly common cause. When stool backs up, it creates pressure and distention throughout the colon, producing dull, widespread abdominal pain that can feel quite intense. Many people don’t connect constipation to stomach pain because the discomfort is higher up than they’d expect.
Food poisoning and stomach viruses cause pain through inflammation of the stomach and intestinal lining. The pain is usually accompanied by nausea, vomiting, or diarrhea and resolves within one to three days.
Acid-Related Pain
Acid reflux and ulcers are among the most common reasons for recurring stomach pain. Your stomach produces hydrochloric acid to break down food, and normally, a mucus lining protects the stomach wall from that acid. When that protective barrier breaks down, or when acid travels upward into your esophagus, pain follows.
With acid reflux, stomach acid literally burns the tissue lining your esophagus. That’s why it produces a burning sensation in the chest or upper abdomen, sometimes intense enough to mimic heart pain (the nerves in your esophagus and heart share the same pathways to your brain). Over time, chronic reflux can inflame the esophagus permanently and even cause ulcers to form there.
Stomach and duodenal ulcers produce a gnawing or burning pain that often worsens on an empty stomach and improves temporarily after eating. Many ulcers are caused by a bacterial infection (H. pylori) that damages the stomach’s protective lining. Others develop from long-term use of anti-inflammatory painkillers like ibuprofen or aspirin. If you have recurring upper abdominal pain that follows a predictable pattern around meals, an ulcer is worth investigating.
Why Stress Makes Your Gut Hurt
The connection between stress and stomach pain isn’t imagined. Your gut and brain are in constant two-way communication through a dense network of nerves, and stress hormones directly affect how your digestive system functions.
When you’re under acute stress, your body’s fight-or-flight response diverts blood away from digestion and speeds up or slows down gut motility. That alone can cause cramping, nausea, or diarrhea. But chronic stress does something more lasting. Prolonged exposure to stress hormones like cortisol actually remodels the nerve circuits involved in processing pain signals from your gut. Specifically, the brain regions that normally dampen pain signals weaken, while the regions that amplify pain signals grow stronger and more connected. The result is visceral hypersensitivity: your gut sends normal signals, but your brain interprets them as pain.
This rewiring helps explain why conditions like irritable bowel syndrome (IBS) are so tightly linked to anxiety and stress. People with IBS often have pain that seems disproportionate to any visible problem in their gut, and that’s because the issue is partly in how their nervous system processes sensation. It’s real pain with a real biological mechanism, not something people are making up.
Pain Specific to Women
Lower abdominal pain in women has a whole additional set of possible causes because the uterus, ovaries, and fallopian tubes sit right in the pelvis alongside the intestines. Menstrual cramps are the most obvious example, but several gynecological conditions can mimic or overlap with digestive pain.
Ovarian cysts, fluid-filled sacs that form on the ovaries, frequently cause one-sided lower abdominal pain that can be sharp or dull. Most cysts resolve on their own within a few menstrual cycles, but a ruptured cyst causes sudden, severe pain. Endometriosis, a condition where tissue similar to the uterine lining grows outside the uterus, causes chronic pelvic pain that often worsens around menstruation and can include bloating, nausea, and pain with bowel movements, making it easy to confuse with a digestive disorder. Pelvic inflammatory disease, usually caused by sexually transmitted infections, produces lower abdominal pain along with fever, unusual discharge, or pain during intercourse.
Stomach Pain in Kids
Children complain about stomach pain constantly, and the vast majority of the time, the cause is benign. Constipation, gas, food intolerance, stomach viruses, and even anxiety or emotional stress are the most frequent reasons. Young children who swallow air while eating or crying can develop enough gas to cause real discomfort. Abdominal migraines, which cause recurring episodes of belly pain without a headache, are another underrecognized cause in school-age children.
Less commonly, stomach pain in kids can signal something more serious: appendicitis, bowel obstruction, or intussusception (where one part of the intestine telescopes into another, most common in children under three). A child whose pain is severe, localized to one spot, accompanied by vomiting that won’t stop, or who refuses to move or walk because of the pain needs prompt evaluation.
Signs That Need Urgent Attention
Most stomach pain resolves on its own or with basic treatment. But certain patterns signal something that can’t wait. Pain severe enough to keep you from functioning normally, vomiting that won’t stop and prevents you from keeping liquids down, or the combination of constipation with escalating pain (which can indicate a bowel obstruction) all warrant an emergency room visit. This is especially true if you’ve had prior abdominal surgery, since scar tissue increases the risk of obstruction.
Blood in your vomit or stool, pain that started suddenly and is getting rapidly worse, or abdominal pain with a high fever are also reasons to seek care quickly. And if you’ve had similar episodes before but this one feels different, more intense, or is accompanied by new symptoms, trust that instinct. Familiar pain that changes character can indicate a new or worsening problem.