Letting air out of an ostomy bag depends on what type of pouch you use, but the basic idea is the same: you open a controlled exit point, press the gas out gently, and reseal. For drainable pouches, you open the tail end over a toilet, angle the pouch so gas escapes first, then close it back up. For closed pouches without a drain, many have a built-in charcoal filter designed to vent gas slowly on its own. When that filter is not enough, or when the bag has ballooned to an uncomfortable size, you need hands-on techniques and sometimes a few product swaps to stay comfortable.
Why Gas Builds Up in the First Place
Your stoma does not have a sphincter. It cannot hold back gas the way your original anatomy could, so every bit of intestinal gas passes straight into the pouch. Some of that gas is swallowed air from eating, drinking, or talking. But a significant portion comes from bacterial fermentation of undigested food residue inside the intestine and even within the pouch itself. A study comparing high-fiber and low-fiber meals in people with ileostomies found that switching from a high-fiber evening meal to a low-fiber one produced a measurable drop in the volume of fermentation gas collected in the bag by the next morning.1Journal of Gastroenterology and Hepatology. Fermentation in ileostomy bags: Control of excessive gas with diet, pH and antibiotics The researchers concluded that most gas in an ileostomy pouch is produced by bacteria fermenting waste inside the bag, not just gas traveling down from the stomach.
This matters practically because it means gas does not arrive all at once. The pouch can be flat after you empty it and then balloon out over the next few hours as fermentation continues. Understanding that cycle helps you anticipate when venting will be necessary rather than being caught off guard at an inconvenient moment.
Venting a Drainable Pouch
If your pouch has an opening at the bottom, releasing gas is straightforward. Head to a bathroom, hold the bottom of the pouch over the toilet, and unclip or unroll the closure. Tilt the pouch so the gas pocket is nearest to the opening. You will hear and feel the air escape. If there is liquid output near the bottom, tip the pouch so the gas rises above it before you open, then slowly angle downward to let the air pass without spilling contents.
A few practical tips make this cleaner. Pressing lightly on the outside of the pouch with your free hand helps push gas toward the opening without squeezing output out in a rush. Some people find that pinching the pouch just above the liquid line creates a temporary barrier so only air escapes. Once the gas is out, wipe the tail, reseal, and tuck the pouch back into your clothing. The whole process takes under a minute with practice. Stoma care nurses stress the importance of patients learning to manage their pouching system confidently, including emptying and wear-time decisions.2ScienceDirect / Seminars in Colon and Rectal Surgery. A stoma nurse’s wishlist to surgeons: Tips for before, during, and after stoma creation
Dealing with Closed Pouches
Closed-end pouches, which are common among people with colostomies, do not have a drain at the bottom. These are designed to be used once and then discarded. Many closed pouches come equipped with an integrated charcoal filter, a small disc built into the pouch wall that lets gas pass through while trapping odor. In comparative testing, filter performance has been identified as one of the key factors users consider when rating pouch quality.3PubMed Central. Ostomy bag management: comparative study of a new one-piece closed bag
In theory, a good filter vents gas continuously so the pouch never balloons. In practice, filters can become clogged with moisture from liquid output, pancaking (when the pouch walls stick together and block airflow), or simply being overwhelmed by the volume of gas produced. When your filter stops keeping up, you have a few options:
- Burp the pouch: Peel up a small section of the adhesive barrier from your skin, just enough to create a gap between the flange and your body. Press the gas out through this gap, then reseal the barrier. This works but risks weakening the adhesive seal if done repeatedly.
- Use an ostomy vent accessory: Several manufacturers sell small adhesive vent plugs that you can stick onto the pouch wall. You puncture a tiny hole in the pouch, apply the vent with its charcoal filter over the hole, and gas escapes through the filter. When you need to vent, you open the plug, press out the air, and close it again.
- Switch to a drainable pouch: If gas is a constant problem, some people find that switching to a drainable pouch, even with a colostomy, gives them more control. You lose the convenience of a sealed bag, but you gain the ability to vent whenever you need to without fiddling with the adhesive.
The “burp” method is the most common improvised solution, but it has limits. Every time you peel back the barrier, you stress the adhesive and risk a leak. If you find yourself burping the pouch more than once or twice a day, it is worth talking to your stoma nurse about a pouch with a better filter or an add-on vent.
Venting at Night
Nighttime is when gas buildup catches many people off guard. You are lying down, so the pouch cannot hang freely, and any gas that accumulates presses against the seal. A pouch that balloons while you sleep can break its seal, leading to a leak on your bedding. It can also wake you up with discomfort or an audible pop if the filter gives way suddenly.
People who struggle with overnight gas often use a larger-capacity pouch for sleeping, giving the gas more room before pressure builds. Wearing the pouch slightly to the side rather than directly on top of you when lying on your back helps gas distribute rather than pooling against the seal. Some people set a quiet alarm to get up once during the night and vent, though this is obviously not ideal for sleep quality. A more sustainable fix is addressing gas production itself through dietary changes, which is covered below.
Reducing Gas So You Vent Less Often
Venting is a management strategy. Reducing the amount of gas your body produces in the first place is prevention. The foods most commonly linked to increased ostomy gas are the same ones that cause gas in anyone: beans, lentils, cruciferous vegetables like broccoli and cauliflower, onions, carbonated drinks, and beer. But for people with a stoma, the effect is amplified because there is no colon (in the case of an ileostomy) or no rectum (in the case of some colostomies) to quietly absorb and release that gas over time.
The fermentation research mentioned earlier found that fiber content was a primary driver of gas volume in ileostomy bags, with a high-fiber meal producing significantly more overnight gas than a low-fiber one.1Journal of Gastroenterology and Hepatology. Fermentation in ileostomy bags: Control of excessive gas with diet, pH and antibiotics That does not mean you need to avoid fiber entirely. It means being strategic about when you eat higher-fiber foods. Eating them at lunch rather than dinner, for example, gives your system more time to process them before bed, reducing overnight ballooning.
Other practical dietary adjustments include eating slowly and chewing thoroughly, which reduces the amount of air you swallow. Drinking still water instead of sparkling water eliminates a direct source of gas. Peppermint tea and yogurt with live cultures are often recommended by stoma nurses, though the evidence for these is more anecdotal than rigorous. Keeping a simple food diary for a couple of weeks can help you identify your personal triggers, since gas production varies a lot from person to person.
Gas, Odor, and Social Anxiety
The mechanical problem of a ballooning pouch is annoying. The social dimension can be genuinely debilitating. In qualitative research exploring quality of life among ostomy patients, some participants described avoiding family gatherings and social events entirely because they feared gas escaping audibly or producing an odor that others would notice. One participant reported not visiting any family member’s home for over two years because of this anxiety.4PubMed Central. Quality of life in ostomy patients: a qualitative study
This kind of withdrawal often stems from early bad experiences or from not yet having reliable techniques for managing gas discreetly. The reality is that once you have a venting routine down and know your dietary triggers, gas becomes manageable rather than unpredictable. If social avoidance has become a pattern, connecting with an ostomy support group or speaking with a counselor who understands chronic illness can help. The fear of what might happen is often worse than what actually happens, but that fear is still real and worth addressing directly.
One thing that helps with both odor and anxiety is using pouches or vent accessories with activated charcoal filters. These do not just release gas; they neutralize much of the smell as the gas passes through. No filter eliminates odor completely, but a functioning charcoal filter reduces it enough that venting in a public restroom stall is usually undetectable to the person in the next stall.
Flying and Altitude Changes
If you have ever noticed your ostomy pouch inflating during a flight, you are not imagining it. As cabin pressure drops during ascent, gas trapped in the pouch and in your intestines expands. Aeromedical transport guidelines note that gas in colostomy and ileostomy bags at ground level will expand with altitude, and that removing a ballooned bag in flight risks faecal overflow. The recommendation is to change to a fresh bag before departure and vent the pouch before removing it during the flight.5ScienceDirect. Practical aspects of aeromedical transport
For commercial air travelers, a few extra precautions make flights smoother. Wear a drainable pouch even if you normally use a closed one, so you can vent into the airplane toilet without fuss. Bring extra supplies in your carry-on, not your checked luggage. Eat lightly before and during the flight, favoring low-fiber, low-gas foods. An aisle seat makes bathroom access easier if you need to vent multiple times. Most experienced ostomy travelers report that once they adapted their routine for flying, it became unremarkable.
Altitude-related expansion is not limited to air travel. Driving through mountain passes or visiting high-altitude destinations produces a milder version of the same effect. If you are heading above about 2,400 meters, keep your venting plan in mind.
Products That Help with Gas Management
Beyond standard pouches and their built-in filters, a small industry of accessories exists specifically for ostomy gas management. Knowing what is available can save you from reinventing solutions on your own.
- Pouch vent inserts: Small adhesive filter patches that stick to the outside of a pouch over a pin-sized hole you make. They let gas escape through charcoal while keeping liquid inside. Brands like Osto-EZ-Vent and similar products are widely available through ostomy supply companies.
- Pouch deodorants: Liquid drops or sprays you add inside the pouch each time you empty or change it. These do not reduce gas volume but neutralize odor, which addresses the social anxiety component.
- Pouch covers: Fabric sleeves that go over the pouch. They do not reduce gas, but they muffle sound when gas shifts inside the pouch and absorb moisture that can clog filters.
- Filter covers and stickers: Small adhesive patches that cover the filter temporarily, such as when you shower or swim. Some people also use them strategically, covering the filter during the day when they prefer to vent manually at set times, and uncovering it at night to allow continuous passive venting while they sleep.
No single product solves the gas problem for everyone. Most people end up with a combination: a pouch they trust, a vent accessory for emergencies, deodorizing drops for confidence, and dietary awareness for prevention. Your stoma nurse is the best resource for product recommendations tailored to your stoma type, output consistency, and lifestyle.
When Gas Signals Something Worth Investigating
Occasional gas is normal and expected. A sudden, persistent increase in gas production, especially if it comes with changes in output color, consistency, or smell, is worth paying attention to. Increased gas can sometimes signal a partial bowel obstruction, a change in your gut bacteria after antibiotics, or a food intolerance that has developed over time. If the change is abrupt and accompanied by cramping, reduced output, or nausea, contact your stoma nurse or physician rather than just adjusting your venting routine.
Persistent foul-smelling gas that does not respond to dietary changes could also indicate bacterial overgrowth in the small intestine, particularly in people with ileostomies. This is treatable but needs a proper evaluation rather than guesswork. The general rule is that if something about your stoma output changes and stays changed for more than a few days without an obvious dietary explanation, it is worth a conversation with your care team.
Sleeping Positions and Pouch Placement
How you position your body affects where gas collects in the pouch and how much pressure it puts on the seal. Lying on your back with the pouch resting on your abdomen tends to be the worst position for gas pressure, because the gas has nowhere to go and presses directly outward against the adhesive. Lying on the side opposite your stoma lets the pouch hang slightly, giving gas room to settle without straining the seal.
Some people use a small pillow or rolled towel alongside their body to support the pouch and prevent it from pulling away from the skin. Others tuck the pouch into a stretchy ostomy wrap or belt that holds it snug against the body. This does not reduce gas, but it prevents the pouch from swinging or shifting when you roll over, which reduces the chance of a seal break during the night. If your current setup leads to regular overnight leaks, experimenting with both sleeping position and pouch support is often more effective than changing pouch brands.