What Causes Abdominal Distension—and How Can You Treat It?

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Medically reviewed by Jay N. Yepuri, MD

Abdominal distension is a noticeable swelling of the belly. Your abdomen can grow larger than normal for a variety of reasons, such as food intolerance, digestive disorder, and gut bacteria overgrowth.

In certain cases, abdominal distension can be relieved with lifestyle and dietary tweaks. However, the symptom can be the result of an underlying health condition that requires medical treatment.

Symptoms of Abdominal Distension

The main characteristic of abdominal distension is having a visibly swollen abdomen. This means the girth, or width, of your abdomen (the area between your hips and chest) is noticeably larger than usual.

If your abdomen is distended, you may also experience abdominal discomfort or pain. You might also notice you are burping or passing gas (farting) more than usual.

Abdominal distension is different from bloating. Bloating is the feeling that you have gas trapped in your abdomen or the sensation of pressure in your abdomen. When you are bloated, your abdomen might feel distended, but it doesn’t look larger. In other words, it’s not distended. However, it is common to experience abdominal bloating and distension at the same time.

What Causes Abdominal Distension?

If your abdomen gets swollen from time to time, it is likely from instances of overeating. You might also realize that your abdomen gets swollen after eating gas-inducing, high-fiber foods like fruits and vegetables. You might also have more gas in your intestines from swallowing too much air while eating, chewing gum, or drinking carbonated beverages.

However, a majority of cases of chronic (long-lasting) abdominal distension are actually not related to gas. Often, there are underlying conditions causing abdominal distension.

The cause of chronic abdominal distension is not always completely understood, and there could be more than one factor leading to it. Here are some of the more common reasons believed to cause abdominal dissension.

Digestive Disorders

Abdominal distension is a common symptom in digestive disorders, including indigestion (functional dyspepsia), irritable bowel syndrome (IBS), constipation, celiac disease. or Crohn’s disease.

While each of these conditions is different, they all impact the way the digestive system functions and so can trigger gastrointestinal symptoms like having a swollen abdomen.

If a digestive disorder is the reason behind your abdominal distension, you’ll likely find that the stomach swelling is long-lasting (chronic) or flares up frequently. You may also notice that bloating happens alongside the abdominal distension and that you experience other symptoms like stomach pain, bowel movement changes, and nausea.

Fluid Buildup

Ascites is a condition that causes a build-up of excess fluid in the abdomen, leading to a swollen stomach. Ascites is usually prompted by an issue with the liver like cirrhosis, where the organ becomes scarred.

With ascites, you may not notice any clear symptoms at first. However, once the fluid starts accumulating, the stomach area will start to appear more swollen. Some people also experience pain and shortness of breath.

Lactose Intolerance

Having an intolerance to lactose means your body isn’t able to digest or break down lactose, a sugar naturally found in milk and milk products. As a result, you experience bothersome and uncomfortable symptoms after eating or drinking food or beverage items like milk, yogurt, and cheese.

A common symptom of lactose intolerance is abdominal distension. In these cases, you’ll experience the swelling shortly after consuming lactose. The distension may come with other symptoms like stomach pain, nausea or vomiting, and diarrhea.

Bacterial Overgrowth

Your abdomen can swell when there’s an overgrowth of normal bacteria in the small intestine, a condition known as SIBO, which stands for small intestinal bacterial overgrowth. The excess gut bacteria can prompt increased gas production, causing the small intestine to expand and making your abdomen feel and appear swollen.

People who have had abdominal surgery or people with certain rheumatic conditions, like rheumatoid arthritis or lupus, might be more likely to experience SIBO. In addition to abdominal distension, symptoms like stomach pain, bloating, and gas may be noticeable.

Cyst or Tumor

When abnormal tissue grows on an internal organ, a tumor or cyst can develop. A tumor may or may not be cancerous. A cyst is a pocket of tissue that can have fluid inside. Either type of growth can lead to visible swelling in the stomach area.

For example, an ovarian cyst—a fluid-filled growth that sits on the ovary—may cause lower abdominal swelling on whichever side the affected ovary is. Most times, though, ovarian cysts don’t cause symptoms.

Uterine fibroids are usually non-cancerous tumors that grow in the wall of the uterus. If they get big, the lower abdomen can grow, though most uterine fibroids won’t cause symptoms.

While it’s a less common cause of abdominal distension, ovarian cancer (cancer that affects tissue of the ovaries) can cause abdominal swelling. You may also experience pain and pressure in the area.

Weak Abdominal Muscles

If your abdominal swelling is apparent when you’re standing up but seems to go away or lessen when you’re lying down, weak abdominal muscles may be the reason for your abdominal distension.

The group of muscles surrounding the abdomen extend from the bottom of the rib cage to both sides of the pelvis, encompassing the entire belly. Abdominal distension related to weak abdominal muscles is more likely to be seen in people who have been pregnant since their abdominal muscles have been stretched and lost tone.

When To See a Healthcare Provider

An occasional case of abdominal distension—like after eating a big meal—is usually not a cause for concern.

But it’s a good idea to consider checking with a healthcare provider if you notice any of the following signs or symptoms:

• Stomach swelling that is getting worse or not going away
• Your stomach area is sensitive to touch
• Fever
• Diarrhea
• Blood in your stool
• An inability to eat or drink normally

Women 55 or older who are noticing abdominal distension along with symptoms like difficulty eating and abdominal, pelvic, or back pain should especially consider getting evaluated to rule out ovarian cancer.

During an office visit, a healthcare provider will likely start by asking questions about your medical history and any additional symptoms, such as:

• Vomiting or nausea
• Diarrhea or loose stools
• Unintentional weight gain or weight loss
• Fatigue
• Excessive gas or burping
• Changes involving your period

They’ll also probably do a physical exam, focusing on the swollen abdomen.

Based on your responses and their physical exam, they may order imaging tests like an abdominal computed tomography (CT) scan, ultrasound, or X-ray. They may also order a colonoscopy to get a look inside your intestines. They may order a blood, breath, or stool test, as well. The tests they order depend on the symptoms you have the cause they suspect.

How To Treat Abdominal Distension

There is no one-size-fits-all treatment for abdominal distension itself. Instead, to relieve the distension and return your abdomen to its regular size, you have to treat the underlying cause.

For cases of abdominal distension related to overeating, you can try eating more frequent, smaller meals. If the swelling comes from gas, you can limit foods that cause gas. If the distension is a reaction to a food your body cannot tolerate well, such as milk, avoid that type of food.

If a digestive issue is causing the distension, there could be a variety of treatment approaches. For instance, a treatment plan for constipation may focus on promoting healthy bowel movements with:

• Hydration
• Exercise
• Increased fiber intake
• Laxatives or prescription medications as needed

Some research suggests probiotics may help improve constipation, but check with a healthcare provider before adding these to your routine.

If IBS is causing your distension, treatment might include:

• Prescription medications
• Dietary and lifestyle changes.
• Therapies that target the connection between the brain and the gut, like diaphragmatic breathing techniques and cognitive behavioral therapy (CBT), a form of therapy that focuses on shifting unhelpful thinking patterns

Ascites can be resolved by treating the underlying cause of the fluid buildup. This may include limiting your fluid intake and taking diuretics to get rid of extra fluid. SIBO is usually treated with antibiotics. Abnormal growths in your abdomen may or may not be treated based on whether they are cancerous or are causing symptoms. Cancerous growths may require surgery or treatment like chemotherapy.

A Quick Review

Abdominal distension is noticeable swelling of the abdomen, or belly. When the distension only happens from time to time, it is most likely due to overeating or gas. But if your abdomen is swollen for the long term, it is more often caused by conditions like digestive disorders, gut bacteria overgrowth, food intolerances, and ascites.

There’s no specific treatment for abdominal distension—the symptom will be managed based on the underlying cause. A treatment plan may include dietary, lifestyle, and medication recommendations.

Read the original article on Health.com.