Clostridium difficile

Clostridium difficile, also known as C. difficile or C. diff, is a bacterium that can infect the bowel and cause diarrhoea.

The infection most commonly affects people who have recently been treated with antibiotics, but can spread easily to others.

C. difficile infections are unpleasant and can sometimes cause serious bowel problems, but they can usually be treated with another course of antibiotics.

Symptoms of a C. difficile infection

Symptoms of a C. difficile infection usually develop when you're taking antibiotics, or when you've finished taking them within the last few weeks.

The most common symptoms are:

  • watery diarrhoea, which can be bloody
  • painful tummy cramps
  • feeling sick
  • signs of dehydration, such as a dry mouthheadaches and peeing less often than normal
  • a high temperature (fever) of above 38C (100.4F)
  • loss of appetite and weight loss

In some cases, serious complications can develop, such as damage to the bowel or severe dehydration, which may cause drowsiness, confusion, a rapid heart rate and fainting.

Who's most at risk of C. difficile?

C. difficile mostly affects people who:

  • have been treated with broad-spectrum antibiotics (antibiotics that work against several types of bacteria) or several different antibiotics at the same time, or those taking long-term antibiotics
  • have had to stay in a healthcare setting, such as a hospital or care home, for a long time
  • are over 65 years old
  • have certain underlying conditions, including inflammatory bowel disease (IBD), cancer or kidney disease
  • have a weakened immune system, which can be because of a condition such as diabetes or a side effect of a treatment such as chemotherapy or steroid medication
  • are taking a medication called a proton pump inhibitor (PPI) to reduce the amount of stomach acid they produce
  • have had surgery on their digestive system

Many C. difficile infections used to occur in places where many people take antibiotics and are in close contact with each other, such as hospitals and care homes.

However, strict infection control measures have helped to reduce this risk, and an increasing number of C. difficile infections now occur outside these settings.

When to get medical advice

Visiting your GP surgery with a possible C. difficile infection can put others at risk, so it's best to phone your GP or NHS 111 if you're concerned or feel you need advice.

Non-urgent advice: Phone your GP if:

  • you have persistent diarrhoea after finishing a course of antibiotics
  • you have bloody diarrhoea
  • you have diarrhoea and experience severe tummy pain, a high fever, a rapid heart rate or fainting
  • you have symptoms of severe dehydration, such as confusion, drowsiness, only passing small amounts of urine or no urine at all

If your GP is closed, phone 111.

Diarrhoea can be caused by a number of conditions and is a common side effect of antibiotics, so having diarrhoea while taking antibiotics doesn't necessarily mean you have a C. difficile infection.

Your GP may suggest sending off a sample of your poo to confirm whether you have C. difficile. A blood test may also be carried out to help determine how severe the infection is, and sometimes you may need tests or scans in hospital to check if your bowel is damaged.

Treatment for C. difficile

Your GP will decide whether you need hospital treatment (if you're not already in hospital). If the infection is relatively mild, you may be treated at home.

If you're in hospital, you might be moved to a room of your own during treatment to reduce the risk of the infection spreading to others.

Treatment for C. difficile can include:

  • stopping the antibiotics thought to be causing the infection, if possible – in mild cases, this may be the only treatment that's needed
  • taking a 10 to 14-day course of antibiotics that are known to kill C. difficile bacteria
  • rarely, serious infections may require surgery to remove a damaged section of the bowel

C. difficile infections usually respond well to treatment, with most people making a full recovery in a week or two. However, the symptoms come back in around 1 in 5 cases and treatment may need to be repeated.

Looking after yourself at home

If you're well enough to be treated at home, the following measures can help relieve your symptoms and prevent the infection spreading.


  • make sure you finish the entire course of any antibiotics you're prescribed, even if you're feeling better
  • drink plenty of fluids to avoid dehydration and eat plain foods such as soup, rice, pasta and bread if you feel hungry
  • take paracetamol for tummy pain or a fever
  • regularly wash your hands and contaminated surfaces, objects or sheets
  • stay at home until at least 48 hours after your last episode of diarrhoea


  • do not take anti-diarrhoeal medication, as this can stop the infection being cleared from your body

Your GP may contact you regularly to make sure you're getting better. Phone them if your symptoms return after treatment finishes, as it may need to be repeated.

How you get C. difficile

C. difficile bacteria are found in the digestive system of about 1 in every 30 healthy adults. The bacteria often live harmlessly because the other bacteria normally found in the bowel keep it under control.

However, some antibiotics can interfere with the balance of bacteria in the bowel, which can cause the C. difficile bacteria to multiply and produce toxins that make the person ill.

When this happens, C. difficile can spread easily to other people because the bacteria are passed out of the body in the person's diarrhoea.

Once out of the body, the bacteria turn into resistant cells called spores. These can survive for long periods on hands, surfaces (such as toilets), objects and clothing unless they're thoroughly cleaned, and can infect someone else if they get into their mouth.

Someone with a C. difficile infection is generally considered to be infectious until at least 48 hours after their symptoms have cleared up.

How to stop C. difficile spreading

C. difficile infections can be passed on very easily. You can reduce your risk of picking it up or spreading it by practising good hygiene, both at home and in healthcare settings.

The following measures can help:

  • stay at home until at least 48 hours after your symptoms have cleared up
  • wash your hands regularly with soap and water, particularly after going to the toilet and before eating – use liquid rather than bar soap and don't use flannels or nail brushes
  • clean contaminated surfaces – such as the toilet, flush handle, light switches and door handles – with a bleach-based cleaner after each use
  • don't share towels and flannels
  • wash contaminated clothes and sheets separately from other washing at the highest possible temperature
  • when visiting someone in hospital, observe any visiting guidelines, avoid taking any children under the age of 12, and wash your hands with liquid soap and water when entering and leaving ward areas – don't rely on alcohol hand gels, as they're not effective against C. difficile
  • avoid visiting hospital if you're feeling unwell or have recently had diarrhoea

Last updated:
29 May 2023