Antigas agents are medicines that relieve the uncomfortable symptoms of too much gas in the stomach and intestines. Excess gas can build up in the stomach and intestines for a number of reasons. Eating high-fiber foods, such as beans, grains, and vegetables is one cause. Some people unconsciously swallow air when they eat, drink, chew gum, or smoke cigarettes, which can lead to uncomfortable amounts of gas in the digestive system. Surgery and certain medical conditions, such as irritable colon, peptic ulcer, and diverticulosis, can also lead to gas build-up. Certain intestinal parasites can contribute to the production of severe gas---these parasites need to be treated separately with special drugs. Abdominal pain, pressure, bloating, and flatulence are signs of too much gas. Antigas agents help relieve the symptoms by preventing the formation of gas pockets and breaking up gas that already is trapped in the stomach and intestines.

Antigas agents are sold as capsules, liquids, and tablets (regular and chewable) and can be bought without a physician's prescription. Some commonly used brands are Gas-X, Flatulex, Mylanta Gas Relief, Di-Gel, and Phazyme. The ingredient that helps relieve excess gas is simethicone. Simethicone does not relieve acid indigestion, but some products also contain antacids for that purpose. Check the product container for dosing information. Typically, the doses should be taken after meals and at bedtime. Chewable forms should be chewed thoroughly. Check with a physician before giving this medicine to children under age 12 years.

Some anti-gas medicines may contain sugar, sodium, or other ingredients. Anyone who is on a special diet or is allergic to any foods, dyes, preservatives, or other substances should check with his or her physician or pharmacist before using any of these products. In addition, anyone who has had unusual reactions to simethicone--the active ingredient in antigas medicines--should check with his or her physician before taking these drugs.

No common or serious side effects have been reported in people who use this medicine. Antigas agents are not known to interact with any other drugs. However, anyone who has unusual symptoms after taking an antigas agent should get in touch with his or her physician.