LAKE TAHOE, CALIF. — Ingesting six capsules of activated charcoal twice a day is the best treatment option for patients with excessive flatus not caused by an underlying treatable condition, Dr. Nirmal S. Mann said at a meeting on gastroenterology and hepatology sponsored by the University of California, Davis.
People normally pass flatus a mean of 15 times per day. Those whose bowels release gas more often or in larger quantities than normal can become socially embarrassed by the sound and smell, start shunning social gatherings, or may even develop marital problems, said Dr. Mann of the university.
Dietary modifications may help, such as avoiding excessive ingestion of beans, cabbage, starch, or complex carbohydrates, which are more likely to cause gas. The over-the-counter product Beano, containing α-galactosidase derived from Aspergillus niger, claims to reduce flatus but does not help, he said.
Lactase-deficient patients should avoid ingesting lactose. One lactose-intolerant patient who passed flatus 134 times in 24 hours solved the problem by restricting lactose in the diet.
The small intestine has a limited capacity to absorb fructose, so patients with excessive gas should avoid high-fructose tropical fruits, such as dates and mangoes, in favor of such low-fructose fruits as cantaloupe.
Artificial sweeteners used in some chewing gum and soft drinks generate more gas, including sorbitol, mannitol, and xylitol. Advise diabetic patients, who are more likely to use these products, to look at product labels if they're complaining of flatus, he suggested.
Sucrose deficiency, a congenital disease, may be the cause of excessive flatus. Consider this diagnosis, especially in children, and treat it with sacrosidase, Dr. Mann added.
Another underlying cause of excessive flatus—small bowel bacterial overgrowth—occurs in about 35% of patients with inflammatory bowel disease. Hydrogen breath tests can detect this problem, which can be treated with antibiotics.
For patients who do not fit into any of the categories above, oral activated charcoal is the best short-term treatment option, Dr. Mann said. He and his associates gave activated charcoal to six patients with excessive flatus and six control patients and measured the number of times they passed flatus in 8 hours, the amount of gas with each release, and bloating scores. All parameters decreased in both groups with treatment.
“Five out of six patients came back thanking me profusely” for reducing flatus, he said. The sixth patient had only a marginal response, so activated charcoal doesn't work every time.
Airtight undergarments containing a charcoal-lined cushion also have been marketed. A recent study found that the cushion made no difference, but the airtight construction contained the smell, if not the sound, of flatus.
“These may not be comfortable [for] sleeping, but if you're trying to avoid a divorce, I think it is a small price to pay,” Dr. Mann said.
Another purported treatment, simethicone, is an organopolysiloxane that produced contradictory results in trials and probably is ineffective.
“I think it just breaks up the bubbles and has no value at all” for reducing flatus, he said.
In the long term, ingesting probiotics may be the most promising strategy for the average patient with excessive flatus. Probiotics may replace bacteria in the gut with bacteria that produce less-odiferous gases.
In patients with lactose malabsorption, prolonged use of lactulose changes the growth of bacteria and reduces malodorous flatus.
Bismuth compounds have been used to control odor from flatus but lead to black-colored stool. “This causes confusion, so I don't recommend that,” he said.
Studies in dogs suggest that zinc acetate might be helpful, but there are no data in humans.
Yucca schidigera also has been studied in dogs but may cause bleeding problems.