Putting on an ostomy bag involves cleaning the skin around your stoma, sizing and cutting the barrier wafer to fit snugly, and pressing the adhesive firmly into place so it seals without gaps. The process takes most people about ten to fifteen minutes once they get comfortable with it, though the first few times can feel clumsy and stressful. Getting the technique right matters more than speed, because a well-applied pouch prevents leaks and protects the delicate skin around your stoma from irritation and breakdown.
What You Need Before You Start
Lay everything out within arm’s reach before you begin. Chasing down supplies mid-change, especially if your stoma is active, turns a routine task into a mess. Here is what you will typically need:
- Ostomy pouch and barrier wafer: either a one-piece system (pouch and wafer fused together) or a two-piece system (separate wafer and snap-on or click-on pouch).
- Measuring guide: a stoma sizing card, usually included in your pouch packaging, or a flexible ruler.
- Curved scissors: small scissors with rounded tips for cutting the wafer opening to size.
- Skin barrier wipes or spray: these leave a thin protective film on the skin before you apply the adhesive.
- Warm water and soft cloths or gauze: for cleaning the peristomal skin. Skip soap with oils or moisturizers, which interfere with adhesion.
- A small trash bag: for the used pouch and wipes.
- Stoma paste or barrier rings (optional): for filling in creases, dips, or uneven areas around the stoma.
Some people like to warm the wafer between their hands or against their body for a minute before application. Body heat softens the adhesive and helps it mold to your skin contours, which improves seal quality. This is especially helpful in cooler rooms or if you store your supplies in a cabinet that stays cold.
Cleaning and Preparing the Skin
Remove your old pouch gently, peeling from top to bottom while pressing the skin flat with your other hand so you are pulling the adhesive away from the skin rather than pulling the skin away from your body. If the adhesive resists, adhesive remover wipes or spray can dissolve the bond without tugging. Once the old pouch is off, use warm water and a soft cloth to clean around the stoma. Pat the area completely dry afterward. Even a small amount of moisture left on the skin will weaken the seal of your new wafer.
This is also the moment to inspect your peristomal skin. Healthy skin around a stoma should look like the skin on the rest of your abdomen. Redness, weeping, raw patches, or small sores are signs that stool or urine has been reaching the skin underneath the wafer, which is the most common form of peristomal skin damage and occurs when effluent from the ostomy causes inflammation and erosion of the skin.1Journal of Wound, Ostomy, and Continence Nursing. Peristomal Moisture–Associated Skin Damage in Adults With Fecal Ostomies: A Comprehensive Review and Consensus If you see these signs, it usually means the wafer opening is too large or the seal has been breaking down before your scheduled change.
Once the skin is clean and dry, apply a skin barrier wipe or spray to the area where the adhesive will sit. These products leave a thin, breathable film on the skin that serves two purposes: it helps the wafer adhere better, and during your next removal, the protective film peels off instead of stripping surface skin cells.2PubMed Central. Prevention of medical adhesive-related skin injury during patient care: A scoping review If you have sensitive skin or change your pouch frequently, a solvent-free barrier formulation tends to cause less redness and irritation over repeated applications compared to solvent-containing versions.3PubMed Central. Effect of a water-based no-sting, protective barrier formulation and a solvent-containing similar formulation on skin protection from medical adhesive trauma Let the barrier film dry for about thirty seconds before moving on. It should feel slightly tacky but not wet.
Measuring and Cutting the Wafer
Your stoma is not a perfect circle, and it changes size, especially in the first several months after surgery when swelling gradually goes down. That is why measuring before every change (or at least regularly) is so important. Hold the sizing guide up to your stoma and find the shape that matches most closely. You want the wafer opening to be about an eighth of an inch (roughly two to three millimeters) larger than the stoma on all sides. Too tight and the wafer presses against the stoma, which can cause irritation or even injury. Too loose and stool or urine pools on exposed skin between the stoma and the edge of the wafer.
If you use a cut-to-fit wafer, trace the correct size onto the back of the wafer with a pen, then cut along the line with curved scissors. The curved tips let you follow rounded edges without accidentally nicking the wafer material. Some people find it easier to fold the wafer slightly before cutting, similar to cutting a paper snowflake, to get a smoother curve. Pre-cut and moldable wafers skip this step entirely. Moldable wafers have a flexible inner ring you stretch with your fingers to match your stoma size, which is especially convenient when your stoma shape is irregular.
Getting this fit right is not a minor detail. Research following stoma patients over two years has shown that regular follow-up and proper adjustment of the appliance are key factors in preventing stoma-related complications.4PubMed. Stoma-related complications and stoma size – a 2-year follow up If your stoma has settled into a stable size after the post-surgical period, you can switch to pre-cut wafers in that size and save yourself the measuring step.
Applying the Barrier Wafer
Peel the paper backing off the wafer. If you are using stoma paste or a barrier ring to fill in skin folds or dips around the stoma, apply those now. Paste goes in a thin bead around the stoma base or into specific creases, not spread across the entire surface. Barrier rings, which are soft moldable strips, press directly around the stoma and act like a gasket.
Position the wafer opening around the stoma, starting from the bottom and working upward. Starting from below gives you a better line of sight, since the pouch will hang downward and not block your view as you settle it into place. Once centered, press the wafer firmly against your skin, starting at the stoma and working outward toward the edges. Use steady, even pressure for about a minute. The warmth and pressure help activate the adhesive. Some people press a hand flat over the wafer and hold it there, while others prefer to smooth outward in a circular motion.
Pay extra attention to the skin directly around the stoma opening. This innermost ring of adhesive is the critical seal. If it does not bond firmly, output will undermine the wafer from the inside and the whole system fails. If you have creases, scars, or folds in the skin near the stoma, you may need to use your fingers to press the wafer into each valley individually.
Attaching the Pouch
If you are using a one-piece system, the pouch is already attached to the wafer, so this step is done. For a two-piece system, line up the flange ring on the pouch with the ring on the wafer. You will hear or feel a click when the two rings lock together. Run your finger around the entire ring to make sure it is sealed evenly all the way around. An incomplete seal here is a common cause of leaks in two-piece systems, and it is easy to miss if you do not check.
Make sure the pouch is positioned the way you want it. Most drainable pouches have a clip or integrated closure at the bottom. Close the tail securely. Some people fold the tail up a few times and secure it with the clip, while newer systems use a built-in fold-and-press closure. Either way, double-check it. An open tail is the most avoidable kind of accident.
Once everything is in place, give the whole system a gentle tug to confirm it feels secure. The wafer should not shift or lift at the edges. If you feel any movement, press those areas again. Some people then place a hand over the pouch and hold gentle pressure against their abdomen for another minute or two to let body heat further bond the adhesive.
One-Piece Versus Two-Piece Systems
The choice between one-piece and two-piece systems is partly about anatomy, partly about lifestyle, and partly about personal preference. One-piece systems are thinner and sit closer to the body, making them less noticeable under clothing. They are simpler to apply because there is no separate attachment step. The trade-off is that every time you change the pouch, you are also removing and reapplying the wafer, which means more adhesive contact with your skin.
Two-piece systems let you swap the pouch without disturbing the wafer. If your skin is sensitive or you need to change pouches more often than every few days, this reduces wear on the skin. The downside is a slightly bulkier profile and the extra step of clicking the pouch onto the flange. People who are active or who swim sometimes prefer two-piece systems because they can pop off the pouch, snap on a smaller stoma cap for brief periods, and then reattach the full pouch later.
Neither system is categorically better. Your stoma nurse can help you try both and see which feels more secure and manageable for your body and your daily routine.
When Standard Flat Wafers Are Not Enough
Flat wafers work well when the stoma protrudes a bit above the surrounding skin and the peristomal area is relatively smooth. But many people have stomas that sit flush with the skin or even retract slightly below it, and others have creases, folds, or hernia-related bulges in the surrounding tissue. In these situations, a flat wafer cannot make consistent contact all the way around, and leaks become a recurring problem.
Convex wafers are shaped with a gentle curve that presses inward toward the body around the stoma opening. This pressure pushes surrounding skin down and helps coax a flat or retracted stoma to protrude slightly, improving the seal. An international consensus panel identified convex products as the preferred approach for managing flat or retracted stomas and for compensating for irregular peristomal skin planes like creases and folds.5PubMed Central. Use of Convexity in Ostomy Care: Results of an International Consensus Meeting Convex wafers come in varying depths, from shallow to deep, and the right choice depends on how much your stoma retracts and how soft the surrounding tissue is. This is a decision best made with your ostomy nurse rather than by trial and error, since too much convexity can cause pressure injuries on the peristomal skin.
How Often to Empty and When to Change
Drainable pouches should be emptied when they are about one-third full. Letting the pouch fill beyond that adds weight that pulls on the wafer, weakens the seal, and increases the risk of leaks. Most people empty several times a day. The process is straightforward: sit on the toilet, open the tail of the pouch, and let the contents drain. Wipe the inside of the tail with toilet paper before closing it back up.
The entire system, wafer and pouch together, typically gets changed every three to five days, though this varies. Some people get a solid week out of a wafer, while others with high-output ileostomies or very liquid stool find three days is the limit. The wafer is telling you when it needs to come off: if the edges start lifting, if you notice output seeping underneath, or if the wafer material has eroded or become mushy near the stoma opening, it is time. Changing on a schedule before you reach the failure point is better than waiting for a leak.
Closed-end pouches, used mostly by people with colostomies who have more formed output, are not drainable. Instead, they are discarded and replaced, sometimes multiple times per day. These tend to be smaller and more discreet, which some people prefer for social situations.
Managing Gas and Odor
Gas buildup can inflate the pouch and make it visible under clothing, a situation people sometimes call “ballooning.” Most modern pouches include a built-in filter that lets gas escape slowly while trapping odor. These filters work reasonably well for a while, but they can become clogged by liquid stool or moisture, at which point gas starts accumulating again. If your filter fails partway through the wear time, you can release gas manually by opening the pouch closure briefly while sitting on the toilet.
Odor is a concern almost every ostomate worries about, often more than the mechanics of the pouch itself. When the system is sealed properly, there should be no odor during normal wear. Odor appears during emptying, during changes, and if the seal is compromised. Pouch deodorant drops or lubricants placed inside the pouch can help during emptying. Researchers have also explored advanced filter designs using activated carbon composites to adsorb specific odor-causing compounds like hydrogen sulfide as they vent through the filter.6Semantic Scholar. A NANOFIBER/ CARBON COMPOSITE FOR OSTOMY VENTS These technologies continue to improve, but in the meantime, a good seal and regular emptying are your best odor management tools.
Protecting Your Skin Over the Long Term
Peristomal skin problems are the single most common complication of living with an ostomy. The damage is not just from the stool or urine itself; it results from a combination of chemical irritants in the output, the pH of the effluent, friction from the wafer, and moisture trapped against the skin.7Journal of Wound, Ostomy, and Continence Nursing. Moisture-Associated Skin Damage That means skin protection is not about any one thing. It is about getting the whole system right: correct sizing so output does not touch the skin, barrier products that shield the skin from adhesive trauma, and a change schedule that does not leave a failing wafer in place too long.
If you do develop skin irritation, resist the urge to change the pouch more frequently than necessary. Each removal-and-reapplication cycle subjects the skin to more adhesive trauma. Instead, address the root cause. If the opening is too large, refit it. If a skin fold is channeling output underneath the wafer, try paste or a barrier ring in that area. If the skin is weeping or raw, a light dusting of stoma powder on the affected area, sealed with a barrier wipe, can create a dry surface for the wafer to adhere to. This “crusting” technique is a standard fix for minor peristomal skin breakdown.
Persistent skin problems that do not improve with these adjustments deserve a visit to your stoma nurse or a wound care specialist. Sometimes the underlying issue is a contact allergy to a component of the wafer adhesive, or a fungal infection in the warm, moist skin under the barrier, and those require different treatments than simple irritation.
Building Confidence With Practice
The learning curve for ostomy care is real. It is normal to feel anxious, frustrated, or overwhelmed during the first weeks, and many people struggle with how the stoma changes their sense of their own body. Research has found a strong link between a person’s confidence in managing their ostomy and how well they adapt to the change in body image: the more capable people felt in their self-care, the less distressed they reported feeling about the stoma.8PubMed Central. Psychological Adaptation to Alteration of Body Image among Stoma Patients: A Descriptive Study In other words, mastering the practical skill of putting on and managing the pouch does more than prevent leaks; it genuinely helps with the emotional adjustment.
Structured education makes a measurable difference too. A study of patients who received a self-care-focused postoperative education checklist found that the checklist was associated with significantly lower odds of hospital readmission after ileostomy surgery.9PubMed Central. Patient autonomy-centered self-care checklist reduces hospital readmissions after ileostomy creation If your hospital or clinic offers a structured teaching program, take it seriously. Ask your stoma nurse to watch you do a full change and give feedback. Having someone confirm that your technique is correct removes a surprising amount of anxiety.
Troubleshooting Common Problems
Even experienced ostomates run into issues. Here are the situations that come up most often and what to try:
- Leaks within a day or two: Almost always a fit or seal issue. Re-measure your stoma, check for skin folds that might be channeling output, and consider whether paste or a barrier ring would help. If you are using a two-piece system, verify the pouch is clicking on completely.
- Wafer edges lifting early: Body sweat, lotion residue on the skin, or an oily skin barrier product can prevent adhesion. Make sure the skin is clean and dry, and avoid moisturizing soaps in the peristomal area. Some people use medical tape or adhesive strips around the wafer edges for extra security during exercise or humid weather.
- Pancaking: This happens when the pouch material sticks to itself and stool collects around the stoma instead of dropping to the bottom of the pouch. A small amount of lubricant or oil inside the pouch before you apply it can help output slide down. Letting a little air into the pouch when you attach it also creates space.
- Skin irritation that keeps returning: If the same spot keeps breaking down, look at whether a crease or scar is creating a channel that output follows. Repositioning the wafer slightly or using a convex product may redirect the flow. Allergic reactions to adhesive components, though less common, cause a distinct pattern of redness that matches the exact shape of the wafer contact area.
Access to a wound and ostomy care team can make a significant difference in outcomes. Research in pediatric patients found that those who were seen by a dedicated wound and ostomy team had significantly fewer hospital readmissions compared to those who were not.10PubMed. Effects of Care Provided by a Wound, Ostomy, and Nurse Team on Hospital Readmission Rates Among Pediatric Patients with Complex Wounds and Ostomies While that study focused on children, the principle applies broadly: having a knowledgeable professional review your technique and troubleshoot persistent problems prevents complications from snowballing. If your current approach is not working, do not assume it is just something you have to live with. Reach out to a stoma nurse, because there are almost always adjustments that can help.