C. Diff: What It Is, Causes, Symptoms & Treatment

C. Diff: What It Is, Causes, Symptoms & Treatment
Adobe Stock
Medically Reviewed By:
Mark Arredondo, M.D.

C. diff (Clostridioides difficile) is bacteria that causes about 500,000 infections a year in the United States, according to the U.S. Centers for Disease Control and Prevention (CDC). It can have mild to severe health consequences.

Discover what C. diff infection is, how you get it, and its symptoms, causes and potential long-term health impacts. Learn about C. diff testing, treatment, precautions and what to expect after you’ve had the condition.

What is C. diff?

C. diff are bacteria that can cause C. diff infection, according to StatPearls. These infections may cause diarrhea and colitis (chronic inflammation of the colon).

How is C. diff spread?

Fecal matter (poop) contaminated with C. diff can get on the skin and into your digestive system. The transfer of these germs usually happens from skin-to-skin contact, the CDC says, although inactive C. diff can also live on objects and in soil. They “activate” again when they get inside your digestive tract.

C. diff causes

Here are four top causes of C. diff infection:


The CDC notes that your risk of C. diff infection increases when you take antibiotics. This is because antibiotics not only kill bad germs but also the good germs that fight harmful bacteria.

“Studies show that you’re seven to 10 times more likely to get C. diff while you’re taking antibiotics or right after,” family medicine specialist Dr. Daniel Allan told the Cleveland Clinic.


Being hospitalized is a major risk factor for C. diff infection, according to Harvard Health. This is because hospital patients are often prescribed medications like antibiotics and may be in close contact with other patients who are infected.

Weakened immune system

People with health conditions that affect the immune system, such as cancer or HIV, are also at increased risk for C. diff infection. The CDC says the same is true for anyone taking immunosuppressant drugs.

People aged 65 and older are also at greater risk, in part because they may be taking medications such as antibiotics and immunosuppressants, or they may have an underlying health condition. The immune system naturally slows down as people age, making it less able to protect against infections, according to Medline Plus.

Previous C. diff infection

One in 6 people who have had a C. diff infection in the last two to eight weeks will be reinfected, according to the CDC.

Is C. diff contagious?

Yes, C. diff bacteria is contagious. StatPearls says it’s primarily transmitted by contact with fecal matter that gets into the mouth and then the digestive system.

Is there a C. diff test?

NYU Langone notes that there are several tests for C. diff, and a stool test is the simplest. You provide a sample of your stool, and a pathologist studies it in a lab to see if it contains C. diff.

Additional diagnostic methods include:

  • Blood tests to check for signs of infection

  • A colonoscopy or sigmoidoscopy to look inside for signs of inflammation

  • CT scan to look for C. diff complications

C. diff symptoms

The Cleveland Clinic lists these as some symptoms of C. diff infection:

  • Watery diarrhea, three or more times a day

  • Bloody stool as infection worsens

  • Swollen abdomen

  • Stomach pain

  • Nausea and vomiting

  • Fast heart rate

  • Fever

  • Lack of appetite

Since other issues may cause similar symptoms, many people want to know, what does C. diff poop look like? It’s usually a bit more solid than normal diarrhea, could have a greenish color and is more mushy than watery.

C. diff treatments

If you’re on antibiotics, the first step to treating a C. diff infection is stopping them. If that doesn’t work to clear up the infection, C. diff medication may be prescribed, according to StatPearls and the Cleveland Clinic.

These are the antibiotics that are considered effective against C. diff:

  • Vancomycin

  • Fidaxomicin

  • Intravenous metronidazole

For more severe or recurring C. diff, different antibiotics may be given, or a fecal transplant may be performed. This is a transplant of healthy fecal bacteria into the intestine.

Long-term problems after C. diff

According to the Cleveland Clinic, after C. diff infection you may experience:

  • Recurring C. diff infections

  • Damage to the intestinal lining

  • Autoimmune disorders

Once you have C. diff, do you always have it?

The National Health Service in the United Kingdom says that C. diff bacteria live in the digestive tract of about 1 in 30 healthy people. It’s only when “good” bacteria that keep C. diff numbers in check are low that C. diff becomes an infection.

“Even after treatment, you may still have small amounts of C. diff in your body that could test positive," Allan said. "If you feel better, you don’t need additional testing or treatment.”

C. diff precautions

The CDC says these are some of the best ways to prevent a C. diff infection:

  • Wash your hands regularly with soap and water

  • Launder bedding, clothing and linens regularly

  • Clean all surfaces with standard disinfectants

Living with C. diff

You can return to normal work, school and social routines once you’ve received treatment and have stopped noticing C. diff infection symptoms. The CDC recommends following the C. diff precautions and working with your doctor to avoid unnecessary antibiotics. These measures can help keep C. diff away so you remain healthy after an infection.


U.S. Centers for Disease Control and Prevention: C. diff (Clostridioides difficile)

U.S. Centers for Disease Control and Prevention: Clostridioides difficile Infection

Cleveland Clinic: How to Prevent C. Diff When Taking Antibiotics

Cleveland Clinic: C. diff (Clostridioides difficile) Infection

Harvard Health Publishing: Preventing C. diff in and out of the hospital

Medline Plus: Aging changes in immunity

NYU Langone: Diagnosing Clostridium Difficile Infections

UK National Health Service: Clostridium difficile

What This Means For You

Washing hands regularly with soap and water and keeping your home and bedding clean will help you avoid C. diff infection.

Related Stories

No stories found.