Flatulence (Gas)

What is flatulence?

Flatulence is the passage of air or gas from the intestines through the rectum. The air or gas is called flatus.

It is normal to have some flatulence. The average person passes gas through the rectum 8 to 20 times a day. Flatulence is usually a problem only when the gas smells foul, happens frequently, or occurs at inconvenient times.

How does it occur?

Part of the flatus in the intestine is air that you have swallowed. You may swallow large amounts of air with your food, especially if you eat or drink quickly. Some people have a nervous habit of swallowing air all day, especially in times of stress. If you are in an upright position, swallowed air can pass back up from your stomach and be released through your mouth in a belch. However, each time you belch, you swallow more air, so the belching is likely to continue. When you lie down, the air may instead pass on through the intestines and rectum and out the anus.

The other cause of gas in the intestines is the digestive process itself. Bacteria in the intestines produce gas as they break down food residues. Some foods are more likely to produce intestinal gas than others, and some medicines that cause constipation can make intestinal gas more frequent or painful. Gas formed by bacteria in the digestive process is always passed through the rectum.

What are the symptoms?

The symptoms of flatulence are:

frequent expulsion of gas through the anus
abdominal discomfort that is relieved by expulsion of gas.

How is it treated?

Flatulence can be treated with the following measures:

Try to eat and drink more slowly so you swallow less air with your food.
Change your diet. Avoid foods that are known to cause excessive gas.

How can I take care of myself?

You should first realize that some flatulence is normal. Try not to let it bother you. The more you worry about it, the more air you are likely to swallow.

Recognizing that you are swallowing air is the first step in controlling the habit of swallowing air. Chew your food longer and sip fluids slowly. Try to avoid frequent sighing and chewing gum.

A change in diet often can help you have less intestinal gas. Try to eat a more varied diet and avoid foods that cause flatulence. These foods vary from person to person, but the following foods commonly produce gas:

dairy products (except yogurt)
vegetables such as brown beans, cauliflower, peas, Brussels sprouts, broccoli, cabbage, mushrooms, and onions
bran and whole grains
fruits like pears, apples, and peaches
carbonated beverages, sparkling drinks, and beer
dried fruits
sugar substitutes in sugar-free foods and candies; for example, sorbitol.

A change in eating habits and diet usually takes care of most gas problems. Many nonprescription medicines are available to help reduce symptoms, including antacids with simethicone and activated charcoal. Digestive enzymes, such as lactase supplements, help digest carbohydrates and may allow you to eat foods that normally cause gas. If the condition continues, however, see your health care provider to check for other possible causes, such as other medicines you are taking.

Disclaimer: This content is reviewed periodically and is subject to change as new health information becomes available. The information provided is intended to be informative and educational and is not a replacement for professional medical evaluation, advice, diagnosis or treatment by a healthcare professional.

HIA File DIG4030F.HTM Release 9.0/2006