Gas (Flatus)

Overview

Gas (flatus) is made in the stomach and intestines as your body breaks down food into energy. All people pass gas, some people more than others. It is normal to pass gas from 6 to 20 times per day.

What are common causes of gas?

Common causes of gas include:

• Swallowed air. If swallowed air is not burped up, it passes through the digestive tract and is released through the anus as flatus. Excessive air swallowing may cause hiccups.
• Foods and drinks such as beans, broccoli, carbonated drinks, and beer. The amount of gas and the odor that different foods cause vary from person to person.
• Lactose intolerance. A person who can't easily digest lactose, a type of natural sugar found in milk and dairy products, can have both gas and bloating as well as other symptoms.
• Constipation. This can cause bloating but generally does not increase gas.
• Medicines or nutritional supplements. Both prescription and nonprescription medicines, as well as dietary supplements, can cause bloating and gas as side effects.
• A medical condition, such as a bowel obstruction or Crohn's disease.
• Changes in hormone levels. It is common for people to have bloating right before their periods because their bodies retain fluid.
• Pregnancy.

How can I prevent it?

You may be able to prevent gas by changing your eating and drinking habits.

Examples of gas-producing foods are:

• Vegetables such as artichokes, asparagus, broccoli, brussels sprouts, cabbage, cauliflower, cucumbers, green peppers, onions, radishes, and raw potatoes.
• Peas, lentils, and beans.
• Fruits such as apricots, bananas, melons, peaches, pears, prunes, and raw apples.
• Wheat and wheat bran.
• Eggs.
• Carbonated drinks, fruit drinks, beer, and red wine.
• Fried and fatty foods.
• Sugar and sugar substitutes.
• Milk and other dairy products, especially in people who have trouble digesting lactose, the main sugar found in milk.
• Packaged foods that contain lactose, such as breads, cereal, and salad dressing.

Dietary enzymes such as Beano may help to prevent gas.

Some people get relief from gas from products containing simethicone, a medicine that dissolves gas bubbles. Nonprescription medicines with simethicone include Gas-X and Mylicon.

Antacids, such as Maalox Anti-Gas and Mylanta Gas, can relieve bloating by making you burp. Be careful when you take over-the-counter antacid medicines. Many of these medicines have aspirin in them. Read the label to make sure that you are not taking more than the recommended dose. Too much aspirin can be harmful.

Occasionally gas is a symptom of a medical condition that requires treatment.