There are many causes of abdominal bloating, including fluid retention, irritable bowel syndrome, and infection. However, for most people, the cause of bloating is harmless and can be treated at home.

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Abdominal bloating — an uncomfortable, full feeling in the belly area — can be alarming, particularly when painful. The abdomen can look larger than usual or be shaped abnormally. Persons may also have piercing abdominal pain. Yet, most times, the cause may just be indigestion or gas building up in the stomach and gut.

Usually, bloating is not a concern if it:

  • is associated with food or eating
  • does not get worse with time
  • goes away within a day or 2

In this article, we look at the causes of abdominal bloating, treatments, and how to know when to see a doctor.

Abdominal bloating is common. Many people experience the same type of bloating again and again. Normally, bloating that follows a predictable pattern is not a worry.

When the pattern changes or bloating becomes worse than expected, it may be one of the following conditions:

Gas

A buildup of gas in the stomach and intestines is among the most common causes of bloating. Other symptoms include:

  • frequent burping
  • passing too much gas
  • feeling a sudden urge to pass stool
  • feeling nauseous

Bloating caused by gas may cause mild discomfort up to intense pain. Some people describe feeling that there is something trapped inside their stomach.

Possible causes of gas include:

  • certain foods, including carbonated beverages, dairy, beans, cauliflower, broccoli, and cabbage
  • swallowing air while eating or chewing gum
  • a stomach infection
  • chronic illnesses, such as celiac disease or irritable bowel syndrome (IBS)
  • indigestion

In most cases, gas goes away on its own after a few hours.

Indigestion

Indigestion, sometimes called dyspepsia, is discomfort or pain in the stomach that can include bloating. Most people experience brief episodes of indigestion from time to time.

It is often caused by:

  • eating too much
  • drinking excessive alcohol
  • taking medications that irritate the stomach, such as ibuprofen
  • a minor stomach infection

Frequent indigestion with bloating that does not appear to be associated with food or other apparent causes could be a sign of something more serious. Potential serious causes include a stomach ulcer or stomach cancer.

Infection

Stomach infections can cause bloating, which may be accompanied by:

These can be caused by bacteria such as Escherichia coli or Helicobacter pylori — or a viral infection such as norovirus or rotavirus.

Stomach infections usually go away on their own after a few days. However, some people may become severely dehydrated or continue to get worse over several days.

These individuals should see a doctor if the bloating coincides with:

  • fever
  • bloody stool
  • severe and frequent vomiting

Small intestinal bacterial overgrowth (SIBO)

The stomach and intestines are home to various bacteria, which help the body digest food. Disturbing the balance of bacteria can lead to an increase in harmful bacteria in the small intestine. This is known as small intestinal bacterial overgrowth or SIBO.

SIBO can cause bloating, frequent diarrhea, and difficulties digesting food and absorbing nutrients. These chronic symptoms may lead to osteoporosis or weight loss in some people.

Fluid retention

Salty foods, changes in hormone levels, and food intolerances can cause a person’s body to hold more fluid than it would otherwise. For instance, some females may become bloated right before their periods or early in pregnancy.

Chronic bloating caused by fluid retention could have a more serious cause, such as liver or kidney failure or diabetes. If the bloating does not go away, a person should speak with a doctor.

Food intolerances

Some people become bloated after eating certain foods — for example, people who have lactose intolerance, gluten allergy, or celiac disease. Bloating can be linked to diarrhea or stomach pain and will go away by removing the problem-causing food.

Chronic disorders

Crohn’s disease and IBS often produce bloating. Crohn’s disease digestive tract inflammation and has a specific course and treatment. In contrast, the cause of IBS is unknown and is often diagnosed when there is no specific reason for symptoms.

Both IBS and Crohn’s can cause gas, diarrhea, and vomiting. If a person is also experiencing unexplained weight loss, they’re more likely to have Crohn’s disease.

Gastroparesis

Gastroparesis is a disorder that affects regular stomach emptying. As a result, the nerves that regulate stomach motion stop working correctly, which causes food to pass much more slowly through the stomach and intestines.

Symptoms include:

  • bloating
  • constipation
  • feeling full quickly when eating
  • loss of appetite
  • heartburn
  • nausea and vomiting
  • pain and discomfort

Diseases such as diabetes or hypothyroidism sometimes cause gastroparesis.

Gynecological disorders

Some gynecological problems cause bloating, such as a monthly period or menopause. Also, endometriosis — in which the womb lining attaches to the stomach or intestines — can cause bloating, cramping, and stomach pain.

Women with early ovarian cancer may have bloating as the only symptom of a problem. However weight gain, constipation, and pain could also occur.

Constipation

Bloating begins when food contents build up in the gut. This condition — called constipation — can come from:

  • dehydration
  • not enough fiber in the diet
  • food intolerance
  • pregnancy
  • certain bowel disorders
  • nutrient deficiencies, including magnesium
  • certain medicines

In most people, laxatives, exercise, drinking water, or changing the diet can resolve episodes of constipation and bloating.

Other causes

Less commonly, abdominal bloating may be due to other serious conditions. People with gallstones or gallbladder disease may experience intense abdominal pain that mimics bloating.

Ascites, a pool of fluid in the abdominal cavity is another condition that leads to abdominal pain and bloating. The most common cause of this fluid buildup is liver disease.

Bloating can usually be safely treated at home by using lifestyle changes, home remedies, or over-the-counter (OTC) medications.

Keeping a food diary to monitor bloating is helpful as this aids with diagnosing food intolerances and making healthy lifestyle changes. Many people find that avoiding certain foods prevents bloating and other gastrointestinal health issues.

Some options that may help include:

Lifestyle changes

Home remedies

  • eating peppermint
  • drinking a mixture of baking soda and water
  • drinking apple cider vinegar
  • applying a heating pad to the stomach

OTC medications

These include:

  • antigas products to break up gas pockets (simethicone)
  • food supplements to break down problem proteins or sugars (Beano, Lactaid)
  • antacids to calm excess acid (Tums, Mylanta, Maalox)
  • bismuth salicylate to inhibit bacterial infection (Pepto-Bismol)
  • laxative to relieve constipation (Ducolax or Senakot)
  • rectal suppository or enema to have a bowel movement (Fleet)

Prescription medications

A doctor may also prescribe:

  • antispasmodics can relax the muscles and help relieve bloating
  • certain antibiotics in cases of IBS or bacterial overgrowth in the abdomen
  • prokinetics can speed up digestion, which may reduce bloating
  • certain antidepressants such as citalopram (Celexa) may help reduce bloating

Rarely, bloating is a sign of something more serious. A person should see a doctor for bloating or gas associated with:

  • intense pain
  • a fever
  • vomiting lasts longer than 24 hours
  • difficulty keeping food down
  • bloody stools
  • a physical injury, such as a punch to the stomach or a car accident
  • rapid swelling of the abdomen
  • surgery
  • liver or kidney failure

Abdominal bloating can be upsetting and painful. There are many simple causes of abdominal bloating, such as gas, constipation, indigestion, food intolerance, and fluid retention.

These symptoms are easily treated with home remedies, lifestyle changes, OTC medications, and prescription medications.

For most people, the cause can be treated at home and is something simple. A person should speak with a doctor if the symptoms worsen or do not go away after a few days.

When should I be worried about bloating?

If bloating patterns have changed suddenly or are getting worse for no reason, a person should see a doctor. Bloating with bloody stools, fever, intense pain, inability to eat, or frequent vomiting can be serious and need urgent care.

What relieves abdominal bloating?

Treat causes of abdominal bloating with home remedies or OTC medications. For example, try walking or moving around, using an antacid or antigas medicine, drinking some water, or using a heating pad.

Why do I look pregnant from bloating?

A swollen belly that looks like pregnancy can be from a condition called ascites. This condition can be related to liver problems, so it is essential to get urgent care.

What causes lower vs. upper abdominal bloating?

Upper abdominal bloating may be related to slow movement of the intestine called gastroparesis, swallowing air while eating, an infection, or overeating. Lower abdominal bloating can be from constipation, IBS, gas caused by food intolerance, or fluid retention.

I have had a sudden change in bowel movements and have frequent bloating. What could this be?

The doctor should check for any sudden changes in bowel habits with bloating. In rare cases, these symptoms could be related to ovarian cancer or colon cancer.

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