The Clostridium Difficile (C. Diff) Bacteria

Medically Reviewed by Shruthi N, MD on July 10, 2024
Written by WebMD Editorial Contributors
9 min read

Clostridium difficile (C. diff) is a type of bacteria that can cause colitis, a serious inflammation of the colon. Infections from C. diff often start after you've been taking antibiotics. It can sometimes be life-threatening.

When you have C. diff, the symptoms can range from mild to severe.

Mild symptoms can include problems such as:

  • Watery diarrhea that happens three to four times a day for several days
  • Stomach pain, cramping, or tenderness

In more serious infections, there may be blood or pus in the stool. This can happen because C. diff can cause the colon (also called the large intestine) to get inflamed. When this happens, tissue in the colon can bleed or make pus. Other symptoms of a serious infection include:

If your C. diff infection is severe, you could get severe intestinal inflammation. Your colon could also get enlarged and you could develop an extreme response called sepsis. All of these problems are serious and could send you to the hospital.

If your diarrhea from C. diff is very severe, get medical help quickly. Severe diarrhea can lead to life-threatening dehydration.

What does C. diff smell like?

C. diff may change the odor of your stool. Some people say it's an unusually strong, foul odor they hadn't noticed before. Others report a sweetness to the odor, which may be caused by bile in your stool.

What does C. diff poop look like?

If you have a condition, such as irritable bowel disease (IBD), that frequently causes diarrhea, it's helpful to know what your diarrhea looks like during a flare. This can help you see differences in the way it looks at other times and seek help promptly. For example, sometimes diarrhea caused by C. diff looks like hot cereal — fluffy or mushy. Sometimes, you might see blood in your stool or mucus. Other times, it might have a green appearance.

C. diff exists all around us. It's in the air, water, soil, and the feces of humans and animals.

C. diff bacteria that are outside the body turn into spores that can live on surfaces for weeks or months. These spores are not "active," but they can turn active after you swallow them and they get into your intestines. Some people have the bacteria in their intestines and never have any symptoms. But for others, the bacteria make toxins that attack the intestines.

A new strain of C. diff bacteria makes larger amounts of toxins. These types are hard to treat with medications.

C. diff bacteria spread in health care facilities, such as hospitals or nursing homes, where workers are more likely to come into contact with them and then with patients or residents.

You can also become infected if you touch clothing, sheets, or other surfaces that have come in contact with feces and then touch your mouth or nose.

Older adults in health care facilities are most at risk, especially if they're taking antibiotics. That's because the human body contains thousands of different types of bacteria -- some good, some bad. If the antibiotics kill enough healthy bacteria, the ones that cause C. diff could grow unchecked and make you sick.

The antibiotics that are most linked to a risk of C. diff infection are:

An increasing number of younger people also develop C. diff infections, even without taking antibiotics or being in a hospital. Failure to wash your hands thoroughly after being exposed to the bacteria can lead to infection.

You also have higher odds of getting C. diff if you have:

Women have higher chances of getting C. diff than men. You're also more at risk for the disease if you're 65 or older. And the more times you've had the disease before, the greater your odds of developing C. diff.

If a C. diff infection isn't treated quickly, you could become dehydrated due to severe diarrhea. This loss of fluids might also affect your:

A C. diff infection also can lead to rare problems such as:

Leaking from your colon. Fluid can leak from your colon into the abdominal cavity, resulting in a loss of proteins called albumin from your colon. Low albumin levels can cause leaky blood vessels and swelling in your face, feet, and hands. 

Pseudomembranous colitis. Caused by toxins produced by C. diff, this type of colitis attacks the cells of your intestinal lining, resulting in ulcers and plaques there. 

Reactive arthritis. Severe C. diff may cause joint pain, inflammation and swelling, an immune response that occurs in a small fraction of people with the infection. 

Toxic megacolon. Your colon dilates and can't release gas or stool. This could cause it to swell and rupture. It can be life-threatening without emergency surgery.

Bowel perforation. This is a hole in your large intestines that allows dangerous bacteria to escape. It can lead to a dangerous infection called peritonitis.

Long-term problems after C. diff

The more severe your C. diff infection is, the higher the likelihood of complications. If you get C. diff a second time, there's a 40% chance you'll get it again.

Your colon may heal more slowly if you had a severe form of C. diff, have taken antibiotics for a long period (including for C. diff), are immunocompromised, or are older than 65.

Yes. C. diff is very contagious. Externally, C. diff is transmitted to your gut through your mouth. Many of us already have C. diff in our intestines that other, helpful bacteria keep in check. When antibiotics kill off these helpful bacteria, C. diff can take over in your gut.

The spores C. diff creates are resistant to the types of substances that kill other bacteria such as heat, acid, antibiotics, and disinfectant cleaners. C. diff can live for months on surfaces.

How long is C. diff contagious?

If you're being treated for Clostridium difficile, you should stay away from other people for at least 48 hours after your symptoms disappear. Sometimes, you can have no symptoms but still have C. diff in your colon that can be spread to others. That's why frequent handwashing with warm water and soap is so important. Hand sanitizer does not work on C. diff.

C. diff incubation period

It's not well-known how long the incubation period for C. diff is. Studies have shown the infection can appear anywhere from 2 days to 3 months after you're exposed.

Antibiotics may have triggered your infection, but some types of these drugs target C. diff. They include:

Talk with your doctor about the side effects of these antibiotics.

It's important to replace fluids that you lost from diarrhea. Drink plenty of fluids that have water, salt, and sugar, such as broth and fruit juices.

If there's been damage to your intestines, you may need surgery to remove the affected areas.

C. diff diet

If you have watery diarrhea, eat starchy foods such as:

  • Crackers
  • Potatoes
  • Rice
  • Oatmeal
  • Soup
  • Boiled vegetables
  • Bananas

C. diff recurrence

Sometimes, a Clostridium difficile infection can come back. Studies have shown that the people most at risk for a recurrence of C. diff are:

  • Older (average age 70)
  • Female or people assigned female at birth
  • Those with a history of cancer
  • Previous users of certain types of antibiotics (tetracyclines, cephalosporins, and nitrofurans)

Other studies have indicated that kidney patients on dialysis may have a higher risk for C. diff. This is because dialysis patients often require antibiotics to treat various complications due to their treatment.

Doctors sometimes recommend a treatment to help repopulate the colon with healthy bacteria. It's often done by putting another person's stool in your colon using a device called a colonoscope. The procedure is called fecal microbiota transplant (FMT).

Donors are screened carefully to make sure they're not passing along infections or parasites.

If you're in a hospital or long-term health care facility, you can do several things to protect yourself from C. diff. For example:

  • Ask your health care professionals to wash their hands thoroughly before and after caring for you.
  • Request that all medical equipment be sanitized before being brought into your room.
  • Wash your hands with soap and water after using the bathroom and before eating.

Another way to help prevent C. diff is to avoid unnecessary antibiotics. Talk this over with your doctor and see if there are other treatment options. And don't take antibiotics without a doctor's OK.

Many C. diff infections are mild and short-lived, but others can be quite serious. Take precautions, and don't hesitate to seek medical help if you have symptoms.

C. Diff and probiotics

After having C. diff, it's important to reintroduce "good" bacteria back into your gut. These bacteria, called probiotics, can help limit the growth of C. diff. Fermented foods with live cultures such as yogurt, kefir, miso, and sauerkraut contain probiotics. Probiotics can also be taken as supplements.

There is limited evidence about the role probiotics play in helping to treat or prevent C. diff. Some data suggests that combinations of the good bacteria Lactobacillus and S. boulardii may help prevent C. diff infections in high-risk patients, but more research is needed.

Clostridium difficileis a very contagious bacterial infection that causes symptoms such as frequent watery diarrhea, abdominal cramping, nausea, fever, blood in your stool, and a rapid heartbeat. C. diff usually occurs after a course of certain antibiotics, known as broad-spectrum antibiotics, which kill good and bad bacteria in your gut and allow C. diff to take over. Risk factors for C. diff include being over age 65; a stay in a hospital, nursing home, or long-term care facility where treatment with antibiotics is common; and a history of previous C. diff infection. Severe C. diff can cause serious complications. If you've recently taken a course of antibiotics, see your doctor if you have watery diarrhea for more than a couple of days, develop a fever, or have severe cramping and abdominal pain.

Is it OK to be around someone with C. diff?

You may have to take care of someone with C. diff, but it's important to take precautions. These include isolating the person as much as possible, wearing and promptly throwing away disposable gloves when you care for them, and washing your hands frequently. Some disinfectants don't work on C. diff, but cleaners containing chlorine (bleach) do. Be sure to disinfect any surfaces the person with C. diff touches.

Can C. diff be treated at home?

Yes. If your symptoms are mild,  your doctor will ask you to stop taking the antibiotics that may have caused your C. diff infection and start you on a new course of antibiotics that specifically target C. diff. Most people make a full recovery in 1 to 2 weeks.

How do you get rid of C. diff permanently?

You might always have C. diff in your gut but not get sick or be contagious. If you have multiple infections with C. diff, a procedure called fecal microbiota transplant from a stool sample of a healthy donor can restore bacterial balance in your gut to help ward off C. diff.

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

After being treated, you may still have some C. diff left in your gut, but the balance of other bacteria in your gut should help keep C. diff in check. A C. diff relapse may not be your original infection but a new one.