Gas – flatulence
Gas is air in the intestine that is passed through the rectum. Air that moves from the digestive tract through the mouth is called belching.
Gas is also called flatus or flatulence.
Considerations
Gas is normally formed in the intestines as your body digests food.
Gas can make you feel bloated. It can cause crampy or colicky pains in your belly.
Causes
Gas can be caused by certain foods you eat. You may have gas if you:
- Eat foods that are hard to digest, such as fiber. Sometimes, adding more fiber into your diet can cause temporary gas. Your body may adjust and stop producing gas over time.
- Eat or drink something your body cannot tolerate. For example, some people have lactose intolerance and cannot eat or drink dairy products.
Lactose intolerance
Lactose is a type of sugar found in milk and other dairy products. An enzyme called lactase is needed by the body to digest lactose. Lactose intoler...
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Other common causes of gas are:
- Antibiotics
- Irritable bowel syndrome
Irritable bowel syndrome
Irritable bowel syndrome (IBS) is a disorder that leads to pain in abdomen and changes in bowel movements. IBS is not the same as inflammatory bowel...
Read Article Now Book Mark Article - Inability to absorb nutrients properly (malabsorption)
Malabsorption
Malabsorption involves problems with the body's ability to take in (absorb) nutrients from food.
Read Article Now Book Mark Article - Inability to digest nutrients properly (maldigestion)
- Swallowing air while eating
- Chewing gum
- Smoking cigarettes
- Drinking carbonated beverages
- Talking while eating and eating too rapidly
Home Care
The following tips may help you prevent gas:
- Chew your food more thoroughly.
- Do not eat beans or cabbage.
- Avoid foods high in poorly digestible carbohydrates. These are called FODMAPs and include fructose (fruit sugar).
- Avoid lactose.
- Do not drink carbonated drinks.
- Do not chew gum.
- Eat more slowly.
- Relax while you eat.
- Walk for 10 to 15 minutes after eating.
When to Contact a Medical Professional
Contact your health care provider if you have:
- Gas and other symptoms such as stomach pain, rectal pain, heartburn, nausea, vomiting, diarrhea, constipation, fever, or weight loss
- Oily, foul-smelling, or bloody stools
What to Expect at Your Office Visit
Your provider will perform a physical exam and ask questions about your medical history and symptoms, such as:
- What foods do you commonly eat?
- Has your diet changed recently?
- Have you increased the fiber in your diet?
Fiber
Fiber is a substance found in plants. Dietary fiber, which is the type of fiber you can eat, is found in fruits, vegetables, and grains. It is an i...
Read Article Now Book Mark Article - How fast do you eat, chew, and swallow?
- Would you say that your gas is mild or severe?
- Does your gas seem to be related to eating milk products or other specific foods?
- What seems to make your gas better?
- What medicines do you take?
- Do you have other symptoms, like abdominal pain, diarrhea, early satiety (premature fullness after meals), bloating, or weight loss?
Early satiety
Satiety is the satisfied feeling of being full after eating. Early satiety is feeling full sooner than normal or after eating less than usual....
Read Article Now Book Mark ArticleBloating
Abdominal bloating is a condition in which the belly (abdomen) feels full and tight. Your belly may look swollen (distended).
Read Article Now Book Mark ArticleWeight loss
Unexplained weight loss is a decrease in body weight, when you did not try to lose the weight on your own. Many people gain and lose weight. Uninten...
Read Article Now Book Mark Article - Do you chew artificially sweetened gum or eat artificially sweetened candy? (These frequently contain indigestible sugars that can lead to production of gas.)
Tests that may be done include:
- Abdominal CT scan
Abdominal CT scan
An abdominal CT scan is an imaging method. This test uses x-rays to create cross-sectional pictures of the belly area. CT stands for computed tomog...
Read Article Now Book Mark Article - Abdominal ultrasound
Abdominal ultrasound
Abdominal ultrasound is a type of imaging test. It is used to look at organs in the abdomen, including the liver, gallbladder, spleen, pancreas, and...
Read Article Now Book Mark Article - Barium enema x-ray
Barium enema x-ray
Barium enema is a special x-ray of the large intestine, which includes the colon and rectum.
Read Article Now Book Mark Article - Barium swallow x-ray
Barium swallow x-ray
An upper GI and small bowel series is a set of x-rays taken to examine the esophagus, stomach, and small intestine. Barium enema is a related test th...
Read Article Now Book Mark Article - Blood work such as CBC or blood differential
CBC
A complete blood count (CBC) test measures the following:The number of white blood cells (WBC count)The number of red blood cells (RBC count)The numb...
Read Article Now Book Mark ArticleBlood differential
The blood differential test measures the percentage of each type of white blood cell (WBC) that you have in your blood. It also reveals if there are...
Read Article Now Book Mark Article - Sigmoidoscopy
Sigmoidoscopy
Sigmoidoscopy is a procedure used to see inside the sigmoid colon and rectum. The sigmoid colon is the area of the large intestine nearest to the re...
Read Article Now Book Mark Article - Upper endoscopy (EGD)
Upper endoscopy (EGD)
Esophagogastroduodenoscopy (EGD) is a test to examine the lining of the esophagus, stomach, and first part of the small intestine (the duodenum)....
Read Article Now Book Mark Article - Breath test
Reviewed By
Michael M. Phillips, MD, Emeritus Professor of Medicine, The George Washington University School of Medicine, Washington, DC. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
Azpiroz F. Intestinal gas. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 11th ed. Philadelphia, PA: Elsevier; 2021:chap 17.
Hall JE, Hall ME. Physiology of gastrointestinal disorders. In: Hall JE, Hall ME, eds. Guyton and Hall Textbook of Medical Physiology. 14th ed. Philadelphia, PA: Elsevier; 2021:chap 67.
McQuaid KR. Approach to the patient with gastrointestinal disease. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 123.