Gas
Gas - Let's clear the air
Much to our dismay, most of us are all too familiar with what is known as flatulence, or intestinal gas. We know from firsthand experience that gas can be an ordinary outcome of the digestive process. While gas can be an embarrassment at a dinner party or office meeting, it usually is not a serious concern at the doctor's office.
In rare instances, however, gas may indeed be a symptom of a more serious condition. For some disorders of the gastrointestinal tract, excess gas production may be the most noticeable indication that there is an underlying problem, while in other instances, gas may be only one of a number of troubling symptoms.
If you are bothered by excess flatulence, remember that while it may not be acceptable to discuss it at the dinner table, it is definitely advisable to bring it up with your doctor to rule out the possibility of a more serious problem.
Detailed Description
Two processes produce gas: when you swallow excess air and pass it through your digestive tract, or when bacteria in your intestines ferment undigested carbohydrates. In either case, when gas builds up in the intestine, the body must find a way to release the pressure. When the anal sphincter muscles relax, the pressure release and the body expels the gas. While most gas is odorless, sometimes it has an unpleasant odor due to its particular gaseous composition.
In the case of normal, intermittent flatulence, you can take certain steps to try to reduce your gas symptoms. Certain foods increase gas production. By monitoring the foods you eat, you might notice a change in the amount of gas you produce. You may also want to try some of the nonprescription products containing simethicone, which breaks up gas bubbles in the stomach.
Synonyms
- Flatulence
- Intestinal gas
How Common Is Gas?
Almost everyone has intestinal gas at one time or another, and most of us pass gas fairly frequently. It is thought that healthy individuals release gas anywhere from eight to 20 times a day. While gas can sometimes indicate an underlying condition, this is rare.
Possible Underlying Causes
Most gas forms when undigested carbohydrates sitting in the intestinal tract undergo fermentation. Bacteria cause the carbohydrates to be broken down into hydrogen, carbon dioxide, nitrogen, and methane, which is responsible for the offensive odor that is characteristic of intestinal gas. Swallowing excess air through eating, drinking, or talking too rapidly may also contribute to gas, if you do not first release the air through belching. Gas production may also increase with gastrointestinal tract disorders that block complete digestion and absorption of nutrients, such as lactose intolerance and celiac disease -- also known as gluten enteropathy.
Triggers of Gas
Certain foods, known as gassers, are particularly likely to trigger an episode of flatulence. Swallowing excess air may also contribute to gas if you do not first release it through belching.
Drugs That Can Cause or Aggravate Gas
Gas is a side effect of many drugs, from antibiotics to antivirals to gastrointestinal drugs, depending on your individual sensitivity. Usually it is a harmless side effect that should not arouse serious concern, although it may cause unpleasant odors. However, if the gas is excessive or becomes bothersome, consult your doctor for a remedy.
Diagnosing the Underlying Cause
While gas is usually nothing to worry about, in rare instances it may be a symptom of an underlying disease or disorder. Some of these disorders have certain characteristic symptoms in addition to excess gas, while others usually don't have symptoms, at least in their early stages.
The following conditions may include excess gas among their symptoms, but the presence of gas should not lead you to conclude that you have a more serious disorder. You should not attempt to diagnose yourself with a medical condition even if your symptoms match those characteristic of a certain disorder. If your symptoms concern you, the best thing to do is to seek medical advice. In order to understand your symptoms and reach a diagnosis, your healthcare provider will consider your medical history, what symptoms you have, and the results of a physical examination and laboratory tests.
Gas unaccompanied by other symptoms may be due to:
- Byproduct of digestive process: the vast majority of all intestinal gas is a normal part of digestion
- Carcinoid tumors: intestinal tumors composed of cells similar to neural and endocrine tissues
- Cirrhosis: chronic and progressive scarring of liver cells
- Diverticulitis: inflammation or infection of hernia-like pouches within the colon
- Parasitic infection (e.g., amebiasis): infection by the parasite Entamoeba histolytica due to consumption of contaminated food or water
Gas accompanied by weight loss and greasy stools may be due to:
- Celiac disease (also known as celiac sprue or gluten enteropathy): gluten sensitivity leading to malabsorption in the small intestine
Gas accompanied by bloody stools, abdominal pain, and weight loss may be due to:
- Crohn's disease: inflammatory disease affecting any portion of the digestive tract from the mouth to the anus
- Ulcerative colitis: inflammation of the mucosal layer of the colon and rectum
- Colorectal cancer: malignant cell growth in the colon or rectum
Gas accompanied by pain in the upper right quadrant of the abdomen may be due to:
- Gallbladder disorders: abnormalities in the gallbladder such as gallstones or cancerous growths
Gas accompanied by cramping may be due to:
- Irritable bowel syndrome (e.g., spastic colon): intermittent bouts of constipation and diarrhea
- Lactose intolerance: inability to digest lactose in dairy products
- Malabsorption: inability of the small intestine to absorb nutrients
Diagnostic Procedures
If your physician believes that the gas you are experiencing may be related to another condition, he or she will attempt to diagnose the underlying disorder by performing a physical exam or ordering various procedures such as stool analysis, barium enema, endoscopy, or blood tests.
Goals of Treatment
For most people with excess gas production, the goal of treatment is to minimize the frequency and severity of flatulence. You can take a number of steps on your own to reduce gas, including changing your diet or trying some of the over-the-counter antiflatulence drugs. In rare cases, excess gas may be a sign of a disease or disorder requiring medical attention. If excess gas is accompanied by a change in bowel habits, abdominal pain, unexplained weight loss, or bloody stools, you should seek medical help to determine whether the gas you are experiencing actually indicates an underlying disorder. If a more serious disorder is contributing to excess gas production, the goal of treatment is to remedy the underlying condition.
Treatment Options
No matter what measures you take, it is unlikely that you can prevent gas altogether. Nonetheless, there are still some steps you can take to minimize the frequency or severity of flatulence. Paying attention to your diet is the best way to prevent gas. Eliminating certain gas-producing foods may help decrease your gas symptoms. Taking over-the-counter medications such as simethicone or alpha-galactosidase enzyme (more commonly known by the brand name Beano) may also help relieve gas symptoms.
Drugs most commonly used
- Simethicone (Gas-X, Phazyme, Mylicon)
- Charcoal capsules (CharcoCaps)
- Charcoal and Simethicone (Charcoal Plus, Flatulex)
- Beano
Simethicone works by dispersing and preventing the formation of mucus-surrounded bubbles of gas. Activated charcoal works by absorbing the gas, thereby decreasing its volume.
Dietary modifications
Your diet may play a large role in the amount of gas your body produces. Certain foods may especially contribute to gas production. Since many of these foods are nutritious, try not to eliminate them from your diet. Instead, try to reduce your consumption of gas-producing foods:
- Apples
- Beans
- Bran
- Broccoli
- Brussels sprouts
- Cabbage
- Cauliflower
- Milk (if you are lactose intolerant)
- Onions
Also reduce your consumption of carbonated beverages. In addition, try to make changes in your habits such as avoiding swallowing excess air, and chewing your food more slowly.
Supplements
- Beano: Humans lack the enzyme to digest oligosaccharides, which then ferment in the large intestine, causing gas. Beano is a supplement that contains the missing enzyme. Researchers at UC San Diego fed bean chili to volunteers, some of whose chili contained added Beano. Within six hours, the Beano group produced significantly less gas.[1]
- Acidophilus: Some people notice that they produce less gas if they take supplemental acidophilus. These bacteria flourish in the healthy intestine, but many people are deficient, which interferes with digestion and promotes the formation of gas.
Herbs
Peppermint: This herb and its oil are age-old remedies for upset stomach and gas. In ancient Rome, people ate a sprig of mint after feasts to calm their stomachs. An echo of this practice survives today in the after-dinner mint. German researchers gave 60 adults with digestive complaints -- including gas -- either a standard drug or a peppermint preparation. The herbal preparation provided greater relief with fewer side effects. [2]
]Exercise
- Yoga: A knee-to-chest position may help relieve intestinal gas. Known as "the wind-relieving pose," this posture should be performed while lying flat on your back. Slowly bend each leg to bring the knee up close to the chest and hold your leg there for a count of 10. Repeat this posture five times for each leg.
For more in-depth digestive information, news, and products, visit The Digestive Health Channel.
Last updated October 1999.
Sources
[1] Ganitas, T.G., et al. "Does Beano Prevent Gas? A Double-Blind Crossover Study of Oral Alpha-Galactosidase to Treat Dietary Oligosaccharide Intolerance," Journal of Family Practice (1994) 39:441.
[2] Westphal, J., et al. "Phytotherapy in Functional Upper Abdominal Complaints," Phytomedicine (1996) 2:285.
Preventing Gas
It is part of the natural process of digestion, but if you have excessive gas, you can try some of the following to prevent it:
- Yes, beans cause gas. But you can largely de-gas them by soaking them in plenty of water overnight before you cook them. Soaking beans removes some of their gas-causing oligosaccharides. After soaking, discard that water and cook your beans in fresh water.
- Chew every bite thoroughly. Chewing reduces the size of the chunks of food you swallow. The smaller those chunks, the less likely they are to enter your large intestine undigested, where they will get fermented into gas.
- Lactose intolerance can aggravate gas. Eliminate milk and dairy foods for a week and see if this helps. If it does, consider eliminating them permanently.
- Keep a food diary. Eliminate foods you suspect of causing problems for a week or so, and see it that helps. If it does, consider eliminating them from your diet.
When to Call the Doctor
Consult your doctor if your gas is accompanied by:
- Abdominal pain or cramping and lasts more than one to two days
- Unexplained weight loss
- Unusual or severe pain
- Bloody stools
Websites & Organizations
American Dietetic Association
216 West Jackson Blvd., Ste. 800
Chicago, IL 60606-6995
Phone: 312-899-0040
American Liver Foundation
Phone: 800-223-0179
American Digestive Health Foundation
7910 Woodmont Avenue, 7th Floor
Bethesda, MD 20814-3015
Phone: 301-654-2635
Fax: 301-654-1140
Email: dlee@gastro.org
American Society of Colon and Rectal Surgeons
85 W. Algonquin Road, Suite 550
Arlington Heights, IL 60005
Phone: 847-290-9184
Fax: 847-290-9203
Celiac Disease Foundation
3251 Ventura Boulevard. # 3
Studio City, CA 91604
Phone: 818-990-2354.
Crohn's and Colitis Foundation of America
11th Floor, Park Avenue South
New York, NY 10016
Phone: 800-343-3637
Health World Medical Self Care
National Digestive Diseases Information
Box NDDIC
Bethesda, MD 20892
Phone: 301-468-6344
Nutritional Institution of America
200 West 86th St., Ste. 17A
New York, NY 10024
National Ulcer Foundation
675 Main Street
Melrose, MA 02176
Phone: 617-665-6210
United Ostomy Association
36 Executive Park, Suite 120
Irvine, CA 92714
Phone: 714-660-8624
Sources & Further Reading
Books
Balch, James F. and Balch, Phyllis A. Prescription for Nutritional Healing. Garden City Park, NY: Avery Publishing, 1997.
Bennett, J. Claude and Plum, Fred. Cecil Textbook of Medicine, eds. Philadelphia: W. B. Saunders, 1996.
Fauci, Anthony J. et. al. Harrison's Principles of Internal Medicine, eds. New York: McGraw-Hill, 1998.
Hardman, Joel G. and Limbird, Lee E. Goodman and Gilman's The Pharmacological Basis of Therapeutics eds. New York: McGraw-Hill, 1996.
Hurst, J. Willis. Medicine for the Practicing Physician eds. Stamford, CT: Appleton & Lange 1996.
Murray, Michael T. Encyclopedia of Natural Medicine. Prima, 1998.
Noble, John. Primary Care Medicine ed. St. Louis: Mosby, 1996.
Physicians' Desk Reference. Montvale, NJ: Medical Economics Co., 1998.
Rakel, Robert E. Conn's Current Therapy eds. Philadelphia: W.B. Saunders, 1998.
Taylor, Robert B. Family Medicine: Principles and Practice. New York: Springer-Verlag, 1998.
Tierney, LM, McPhee, SJ, and Papadakis, MA. Current Medical Diagnosis and Treatment eds. Stamford, CT: Appleton & Lange, 1998.
Articles
Bassotti, G, Germani, U, Morelli, A. "Flatus-Related Colorectal and Anal Motor Events." Dig Dis Sci. 41(2):335-8. Feb 1996.
Bond JH, "Relation of food ingestion to intestinal gas production and gas related symptoms." J Environ Pathol Toxicol Oncol, 5(6):157-64 1985 Jul
Bynum, TE. "Hepatic and Gastrointestinal Disorders in Pregnancy." Med Clin North Am. 61(1):129-38. Jan 1977.
Finegold, SM. "Anaerobic Bacteria. Their Role in Infection and their Management." Postgrad Med. 81(8):141-7. Jun 1987.
Ganitas, TG et al. "Does Beano Prevent Gas? A Double-Blind Crossover Study of Oral Alpha-Galactosidase to Treat Dietary Oligosaccharide Intolerance," J. of Family Pract. (1994) 39:441.
Nickas, ME, Reese, JH, Anderson, RU. "Medical Therapy alone for the Treatment of Gas Forming Intrarenal Abscess." J Urol. 151(2):398-400. Feb 1994.
Ogilvie, AL, Atkinson, M. "Does Dimethicone Increase the Efficacy of Antacids in the Treatment of Reflux Oesophagitis?" J R Soc Med. 79(10):584-7. Oct 1986.
Rocco, MV, Gassman, JJ, Wang, SR, Kaplan, R. "Cross-Sectional Study of Quality of Life and Symptoms in Chronic Renal Disease Patients: The Modification of Diet in Renal Disease Study." Am J Kidney Dis. 29(6):888-96. Jun 1997.
Sferra, TJ, Heitlinger, LA. "Gastrointestinal Gas Formation and Infantile Colic." Pediatr Clin North Am. 43(2):489-510. Apr 1996.
Stahlberg, MR. "Infantile colic: Occurrence and Risk Factors." Eur J Pediatr. 143(2):108-11. Dec 1984.
Westphal, J. et al. "Phyotherapy in Functional Upper Abdominal Complaints," Phytomedicine (1996) 2:285.
"Dimethicone for gastrointestinal symptoms?" Drug Ther Bull. 24(6):21-2. Mar 24, 1986.