Expert opinions vary on what a typical colostomy output should be, but some suggest an average of 500 milliliters (2 cups) per day. Changes in stoma output or consistency could signal a complication.

If you’re living with a stoma, your colostomy output will largely depend on what you eat and drink.

The volume and consistency of your stool can affect your health, lifestyle, and comfort level, so it’s important to maintain a colostomy output within the typical range.

In this article, we’ll provide the typical range for colostomy output. We’ll also discuss what can cause your output to be too high or too low, and what you can do about it.

It takes time after a colostomy for your bowels to stabilize and start functioning normally. A healthcare professional may recommend you follow a colostomy diet for several days or weeks after surgery.

At first, you’ll start to pass gas without stool. Your initial post-operative stools will be very loose in consistency. This is typical and not a cause for concern.

Once your bowels start to function regularly, your stool consistency will become thicker and firmer. Some people who have had colostomies say their stool’s consistency remains semi-formed and pasty in texture.

The location of your stoma may indicate the stool consistency you can expect. Stomas placed low in the colon allow for longer digestive periods and are likely to produce firmer stools.

Experts differ on what they consider a typical colostomy output. The American Society of Colon and Rectal Surgeons identifies a typical range as 200–700 milliliters (mL), or about 1–3 cups, with an average of 500 mL (about 2 cups). The United Ostomy Associates of America recommends aiming for a daily output of 600–900 mL (about 2.5–4 cups).

Monitoring your colostomy output can help ensure it stays in the typical range. It can also help you avoid complications like dehydration, constipation, or blockages.

You have a high stoma output if you produce more than 1.5–2 liters a day. Output levels this high are typically watery in consistency.

A high stoma output may require you to empty your appliance many times a day. Based on the type of equipment you have, your pouch may also leak.

Having consistently high stoma outputs puts you at risk of magnesium depletion, dehydration, and malnutrition. Most people with stomas can avoid these risks and reduce their output by making dietary changes.

Certain foods thicken stool, reducing the output. They include:

  • rice
  • tapioca
  • bananas
  • oatmeal
  • white pasta
  • white potatoes without the skin

In some cases, the more colon you have surgically removed, the more challenging it is to change your output volume or consistency.

Your daily stoma output is too low if it’s under 200 mL (less than 1 cup).

You can expect to produce little-to-no ostomy output for a few hours every now and then. This is typical and not cause for alarm. However, a consistently low output for several days may indicate constipation or a blockage in your bowels or stoma.

You should immediately inform a healthcare professional if you have low or no output with abdominal pain for 4 hours or longer.

It’s typical not to have any stoma output for the first 2–3 days after a colostomy. But no output after the initial phase may suggest a problem.

If your stoma output suddenly stops and you also have symptoms like stomach pain, cramps, or nausea, you may have an intestinal obstruction. No output, or clear, watery output that lasts 4 hours or longer, may also indicate a full or partial blockage.

Bowel obstructions may begin with constipation that slows your output for 1 day or longer.

If you have low or no stoma output for more than 12–24 hours, let a healthcare professional know, especially if you have abdominal pain. They may recommend at-home treatments that can alleviate constipation and halt the formation of a blockage, such as:

  • taking prescription laxatives
  • increasing your fluid intake
  • consuming a liquid diet
  • eating certain high fiber foods
  • walking to support bowel muscle movement
  • gently massaging your stoma

Many people with stomas find that, over time, they can resume eating an unrestricted diet. Keeping an eye on your stoma output can help you determine if you are on the right track or need to make modifications.

Monitoring your output can also help you troubleshoot potential problems. You can do this by pouring the contents of your colostomy bag into a measuring cup reserved for this purpose.

Other tips include:

  • Introduce high fiber foods into your diet.
  • Eat frequent small meals throughout the day rather than three large meals.
  • Avoid high fat or sugary foods.
  • Avoid sugar substitutes.
  • Reduce or eliminate alcoholic beverages.
  • Chew your food thoroughly into small, easy-to-digest pieces to reduce the risk of blockages.
  • Sip fluids slowly rather than drinking large quantities in one sitting. Fluid intake is important, but too much at one time may increase ostomy output, causing dehydration.
  • Consider drinking rehydrating beverages, like Pedialyte, throughout the day to reduce dehydration.

What causes a watery stoma output?

Diarrhea (loose, watery stool) can be due to multiple factors, including illness or food poisoning. If you have a stoma, certain foods and drinks can also cause watery output. These include alcohol, whole grains, spicy foods, and raw, cruciferous vegetables.

What color should my stoma output be?

Your stoma output should usually appear brown, as when you eliminated stool naturally. But what you eat may significantly affect the color of your stoma output.

Stomach bile (digestive fluid) that you excrete after having an illness may appear green in your colostomy bag.

Can stoma output be too thick?

It’s possible for your stoma output to be too thick, causing it to stick to the uppermost lining of your pouch rather than dropping to the bottom. This may cause the output to pool around the stoma, irritating your skin.

You may be able to eliminate too-thick stoma output by increasing your fluid intake. If that doesn’t work, let a healthcare professional know.

Experts differ on what a typical daily colostomy output should be, with values ranging from 200–900 mL (about 1–4 cups). An ongoing colostomy output above that range puts you in danger of dehydration or malnourishment. Ostomy output below that range may indicate constipation or bowel obstruction.

Monitoring your output and controlling your diet can help you keep your colostomy output in the typical range. Talk with a healthcare professional to determine what is best for you.