Pseudomembranous Colitis


What is pseudomembranous colitis?

Pseudomembranous colitis is inflammation (swelling, irritation) of the large intestine. In many cases, it occurs after taking antibiotics. Using antibiotics can cause the bacterium Clostridium difficile (C. diff) to grow and infect the lining of the intestine, which produces the inflammation. Certain antibiotics, like penicillin, clindamycin (Cleocin®), the cephalosporins and the fluoroquinolones, make C. diff overgrowth more likely.

Who is at risk for getting pseudomembranous colitis?

People who have the greatest risk for developing pseudomembranous colitis include:

  • Residents of nursing homes
  • People who have been in the hospital for a long time
  • People living with another, severe medical condition

Symptoms and Causes

What causes pseudomembranous colitis?

For some people, C. diff is part of the normal bacterial flora, or the collection of bacteria, in the gastrointestinal tract. Pseudomembranous colitis results from changes to the bacterial flora after you use antibiotics.

In some cases, taking antibiotics can cause C. diff to grow out of control and release toxins (poisons) into intestinal tissues. These toxins attack the lining of the intestine and cause pseudomembranous colitis symptoms.

What are the symptoms of pseudomembranous colitis?

Symptoms of pseudomembranous colitis include:

  • Frequent watery diarrhea that is sometimes bloody
  • Pain and tenderness in the stomach
  • Cramping
  • Nausea
  • Fever
  • Loss of appetite

In more severe cases, sepsis (the body’s potentially dangerous overreaction to an infection) can occur.

Most people who have pseudomembranous colitis notice symptoms 5 to 10 days after starting treatment with antibiotics.

Diagnosis and Tests

How is pseudomembranous colitis diagnosed?

Pseudomembranous colitis is diagnosed by examining a sample of feces (stool) in a laboratory to identify toxins produced by C. diff.

Doctors may diagnose pseudomembranous colitis with a sigmoidoscopy. This procedure uses a thin, flexible tube (sigmoidoscope) that enables your doctor to view the interior of your large intestine.

Management and Treatment

How is pseudomembranous colitis treated?

The first thing your doctor may recommend is that you stop taking the antibiotic that led to the pseudomembranous colitis infection.

Pseudomembranous colitis is treated with antibiotics that target this infection. In most cases, doctors prescribe metronidazole (Flagyl®), vancomycin (Vancocin®) or fidaxomicin (Dificid®) for up to 14 days.

Pseudomembranous colitis recurs (comes back) in as many as 20% of people who have been treated. If this occurs, your doctor will prescribe another dose of an antibiotic.

A newer treatment known as a fecal transplant uses stool from a healthy donor to help restore normal bacterial flora to your intestine, especially if the infection has returned after the first treatment.

What complications are associated with pseudomembranous colitis?

Complications of pseudomembranous colitis include the following:

  • Some people suffer reinfections with C. diff, which can cause pseudomembranous colitis to recur many times.
  • If your C. diff infection worsens, you may become dehydrated (lose a great deal of fluid) from frequent diarrhea. You may also temporarily lose the ability to pass stool.
  • In rare cases, pseudomembranous colitis causes toxic megacolon (severe intestinal distention, or swelling), intestinal perforation (puncture) or sepsis. These conditions are medical emergencies that must be treated immediately.

Call 911 or go to an emergency room if you have signs of these complications, including:

  • Severe abdominal distention (bloating) and pain
  • Rapid heartbeat (tachycardia)
  • Abdominal tenderness


Can pseudomembranous colitis be prevented?

Pseudomembranous colitis from out-of-control growth of C. diff bacteria can be prevented by following basic sanitation practices:

  • Wash your hands often with soap and water.
  • Wash your hands after visiting anyone in a nursing home or hospital.
  • Disinfect surfaces with chlorine bleach-based cleaning products.
  • Don’t use antibiotics except those prescribed by your doctor.
  • If caring for someone with C. diff, wear disposable gloves and wash your hands after all contact.
  • If your clothing becomes soiled with stool from someone infected with C. diff, wash your clothing with soap and chlorine bleach.

Outlook / Prognosis

What is the outlook for people who have pseudomembranous colitis?

With treatment, most people recover fully from pseudomembranous colitis. For a small number of people, reinfection with C. diff can lead to repeated bouts of the illness.

Living With

When should I call my doctor about pseudomembranous colitis?

If you develop symptoms of pseudomembranous colitis, especially if you’ve recently taken antibiotics, contact your doctor for evaluation and treatment.

Last reviewed by a Cleveland Clinic medical professional on 02/26/2018.


  • Centers for Disease Control and Prevention. Clostridium difficile Infection Information for Patients. ( Accessed 3/5/2018.
  • American Academy of Family Physicians. Clostridium difficile (C. diff.) Infection. ( Accessed 3/5/2018.
  • Merck Manual Consumer Version. Clostridium difficile-Induced Colitis. ( Accessed 3/5/2018.

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