Extra mucus in the digestive tracts of people with CF causes stool to move more slowly and slows the production of enzymes, causing blockages and constipation. Laxatives can often help, but severe cases may require surgery.

Cystic fibrosis (CF) is an inherited disease that affects mucous membranes throughout your body. Its most significant effects tend to be on your lungs and digestive system.

Children and adults with CF often experience digestive symptoms such as constipation and bowel obstruction. Keep reading to learn more about how CF contributes to these symptoms and what you can do to manage or even prevent them.

CF causes your body to make thick and sticky mucus. Mucus should act as a slippery lining that protects organs, airways, and the digestive tract. In CF, mucus can cause blockages in organs and passageways.

Digestive enzymes move from the pancreas into the small intestine, where they work with bile from the liver to digest food. In CF, mucus builds up in the tubes that connect the pancreas to the small intestine. The blockage results in pancreatic inflammation, limiting the production of enzymes. This is called pancreatic insufficiency.

Because of pancreatic insufficiency, someone with CF can have many digestive symptoms, including constipation and DIOS.

Distal intestinal obstruction syndrome (DIOS) is a complication of CF that can cause symptoms similar to constipation, like bloating and abdominal pain.

Constipation is when stool builds up in your large intestine (colon). DIOS occurs when mucus and food waste form a mass that obstructs the distal part of your small intestine, where it joins the large intestine.

DIOS affects 10–22% of people with CF. It’s more common in adults than children but can affect both. A blockage from DIOS may be complete or incomplete.

Symptoms of intestinal blockage from DIOS include:

  • pain in the lower right abdomen
  • widening of waist area (abdominal distension)
  • nausea
  • inability to pass stool

Doctors can confirm DIOS with X-rays or other imaging.

Other digestive symptoms of cystic fibrosis

Common digestive symptoms with CF include:

  • nausea and vomiting
  • heartburn (acid reflux)
  • sharp, stabbing, or dull abdominal pain
  • changes to stool color and texture
  • feeling or appearing bloated
  • flatulence or excessive gas
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Parents and people with CF can often resolve constipation or mild DIOS with conservative measures like laxatives. You may want to consult a doctor if you or your child experience severe symptoms.


Polyethylene glycol electrolyte solutions such as MiraLAX or GoLYTELY can relieve constipation or mild DIOS. Parents should look for a pediatric formulation or consult their doctor for the right dose.

Nasogastric tube

A nasogastric (NG) tube goes into your stomach through your nose to drain your stomach. A doctor will place an NG tube in the hospital. Emptying the stomach can prevent you from vomiting bile.

Your doctor may also put you on intravenous fluids. They may also administer laxatives or digestive enzymes orally or through the tube.


In very rare cases, a doctor may recommend surgery for DIOS. Surgical options include small bowel resection, where a surgeon removes part of the bowel.

A doctor may consider surgery if there is loss of blood flow to the intestines (intestinal ischemia). Signs of intestinal ischemia in children are:

  • rapid heart rate
  • fever
  • abdominal tenderness
  • signs of inflammation

Surgery for DIOS is high risk and typically a last resort.

In infants

Doctors may recommend adequate fluid intake and laxatives for infants with CF who have constipation. They also may recommend an ongoing protocol of laxatives to take at home for children under 1 year of age.

Constipation and intestinal blockage can become severe. You may want to consult a doctor if you or your child experience:

  • severe pain that makes regular activity difficult
  • vomiting
  • blood or stool in vomit
  • fever
  • nausea that stops you from eating

Adults and children with CF often take steps to keep their bowels moving. Such steps include:

  • increasing fluid intake
  • taking preventive laxatives
  • eating digestive enzymes with meals
  • exercising regularly

Since CF can change the bacterial balance in the gut, a doctor may prescribe antibiotics. Some people choose to take probiotics to replenish the good bacteria in the gut. Food sources of probiotics include:

It’s a good idea to discuss supplements or diet changes with a doctor.

Children and adults with CF often have constipation. You can often manage symptoms with digestive enzymes, laxatives, and increased fluid intake.

In the case of intestinal blockage, a doctor may use a nasogastric tube to drain your stomach. Surgery is a last resort to treat blockage.