Patient education: Gas and bloating (The Basics)

What causes gas? — Causes of gas include:

●Swallowing air, often while eating, drinking, or smoking. Swallowed air usually comes back out as a burp.

●Eating certain foods, such as beans, broccoli, fruit, wheat, potatoes, corn, and noodles. Bacteria in the intestines digest parts of these foods and spit out gas.

●Trouble digesting certain foods, such as wheat or dairy products

●Conditions that harm the digestive system

What causes bloating? — The colon has a lot of bends in it (figure 1). When air gets trapped in these bends, you might feel cramps or sharp pains. This pain is common in the middle and top of the belly on either side.

How much gas is normal? — Most people pass gas 14 to 23 times each day. Burping before and after meals is also common. Gas bothers some people more than others.

Why does my gas smell? — Most of the gas that comes out of your anus has no smell. But some of it contains a substance called sulfur. Sulfur smells bad to most people.

Is there anything I can do on my own to get rid of gas and bloating? — You might feel better if you:

●Cut down on certain foods. Write down what you eat so you can figure out which foods are causing your gas. Everyone's body is different. Common causes of gas are:

•Milk and dairy products

•Beans

•Some vegetables, such as cabbage, Brussels sprouts, asparagus, broccoli, potatoes, and corn

•Some whole grains, such as wheat

•Most types of fruit

•Artificial sweeteners

•Soda and other fizzy drinks

•Chewing gum

●Take medicines that contain simethicone (sample brand names: Maalox Anti-Gas, Mylanta Gas, Gas-X, or Phazyme). You can get these at a pharmacy. Simethicone breaks up gas bubbles in your intestines. Doctors aren't sure how well it works.

●Take a product called Beano. This can help your body digest beans and some vegetables.

●Take a medicine called bismuth subsalicylate (brand name: Pepto-Bismol). This can help make gas smell less bad.

Should I see a doctor or nurse? — See your doctor or nurse if you also have any of these symptoms:

●Diarrhea

●Unexplained weight loss

●Belly pain

●Blood in bowel movements

●Loss of appetite

●Unexplained fever

●Vomiting

Should I have tests? — Your doctor or nurse will decide which tests you should have based on your age, other symptoms, and individual situation. There are lots of tests, but you might not need any.

The most common tests doctors use to find the cause of gas and bloating:

●Tests on a sample of your bowel movements to check for blood, unusual levels of fat, and other things

●Blood test to see if your body has trouble digesting an ingredient called gluten. Gluten is in bread, pasta, condiments, and other foods.

●Breath test to see if your body has trouble digesting dairy products or if you have an overgrowth of bacteria in your intestines

●X-rays to see if there is something wrong with your intestines

●Upper endoscopy or colonoscopy – For these tests, the doctor puts a thin tube into your stomach or colon. The tube has a camera attached to it, so the doctor can see inside you. The doctor can also take samples of tissue to look at under the microscope (figure 2).

How is gas and bloating treated? — That depends on what is causing your gas and bloating. Treatments can include:

●Changing what you eat and drink

●Changing how you eat and drink. Eating more slowly can help with burping.

●Using supplements to help you digest dairy products

●Taking medicines that you can buy at a pharmacy

●Taking medicines that your doctor prescribes

Can gas be prevented? — You can reduce your chances of getting gas again if you:

●Avoid foods and drinks that make you gassy.

●Take Beano when you eat beans and some vegetables.

●Take supplements that help you digest dairy, if needed.

●Eat more slowly.

More on this topic

Patient education: Stomach ache and stomach upset (The Basics)

Patient education: Gas and bloating (Beyond the Basics)