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Beat the bloat and gas
Roger Selvage 16269

Beat the bloat and gas

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OTCs Today

Mary Warner

Image of green gastric digestion bubbles.

Everyone has gas; producing and passing gas is a normal part of the digestion process. According to Johns Hopkins Medicine, most people produce 1 to 4 pints of gas a day and eliminate excess gas—either by burping or passing gas (flatulence)—about 14 times a day. But when gas is trapped or not moving well through the digestive system, most patients will look for OTC relief of the resulting pain and bloating.

Intestinal gas can be caused by swallowing air, commonly from eating or drinking rapidly; the bacterial breakdown of undigested food in the colon, which produces hydrogen, carbon dioxide, and methane; and some foods such as beans. Lactose intolerance and less common diseases, such as celiac disease, can also cause intestinal gas.

Simethicone, activated charcoal, digestive enzymes, and probiotic products are the most common nonprescription medications for treating intestinal gas. Simethicone and activated charcoal relieve symptoms after gas has formed, while α-galactosidase and lactase enzymes are taken with food to prevent gas from forming.


Simethicone functions as a nonsystemic surfactant, decreasing the surface tension of gas bubbles in the GI tract, which coalesces and disperses the gas bubbles and allows them to be removed via flatulence or belching. FDA approved simethicone in 1952 and considers it safe and effective with no serious adverse effects, although mild diarrhea and nausea have been reported. Because simethicone is not absorbed orally, systemic adverse effects do not occur. 

Simethicone is available as tablets, capsules, chewables, and liquid and is often combined with antiacids (aluminum hydroxide, magnesium hydroxide, and/or calcium carbonate). Common products include Gas-X, Phazyme, and numerous generic medications.

Activated charcoal

Although activated charcoal is promoted for relief of intestinal gas, it is not FDA approved and should be used with caution. It has been suggested that activated charcoal absorbs intestinal gas, but there is limited research into its efficacy. Activated charcoal can result in tongue discoloration, black stools, and constipation, and can interfere with absorption of some medications.

Activated charcoal is available as tablets, capsules, or loose powder. Common products include Charcoal Plus DS, CharcoCap, Nature’s Way, and numerous generic forms.


The enzyme α-galactosidase relieves intestinal gas and bloating by breaking down the carbohydrates in beans and other vegetables. Derived from Aspergillus niger, α-galactosidase hydrolyzes oligosaccharides into their component parts before they can be metabolized by colonic bacteria.

Because high-fiber foods, including legumes, contain large amounts of oligosaccharides, α-galactosidase can prevent excessive intestinal gas associated with high-fiber diets.

Forms of α-galactosidase include tablets, capsules, and orally disintegrating tablets (meltaways), which should be taken immediately before, during, or after a meal. Common products include Beano, Equate, and numerous generics.

Lactase supplements

For those who are unable to digest lactose, lactase supplements are available to prevent gas and bloating that may occur after eating dairy products. Lactase breaks down lactose into glucose and galactose, which can be absorbed. No adverse effects have been reported.

Lactase is available as a powder and liquid drops that can be added directly to dairy products and as capsules and tablets that are taken before eating dairy products. Common products include Lactaid, Dairy Aid, and Nutricost.


Some patients have reported that probiotic supplements, containing Bifidobacterium, Lactobacillus, Saccharomyces, or Streptococcus thermophilus, alone or in combination, have eased their gas and bloating symptoms by introducing new bacteria into the digestive system. Because probiotic bacteria leave the intestine soon after their use is discontinued, daily administration is required to maintain the bacterial populations in the intestines. A trial of 14 days is generally recommended for patients starting a probiotic regimen.

What to tell your patients

Advise patients who complain of gas and bloating to avoid foods and drinks that introduce gas into the digestive system. If symptoms persist, lactase or α-galactosidase can be taken with food to prevent intestinal gas from forming.

Simethicone can be taken after symptoms occur, but patients should be advised to discontinue use if relief isn’t achieved within 24 hours. If patients have other symptoms, they should be advised to consult a physician to determine what is causing the pain.

For further information, see Chapter 14 in APhA’s Handbook of Nonprescription Drugs, available in the bookstore on or in Pharmacy Library.



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