Because CDI is frequently seen in individuals taking antibiotic medications to treat other infections, it is important to stop taking all antibiotics other than those prescribed by the doctor to treat CDI (the doctor will explain which antibiotics to take and which to stop). This is because taking other antibiotics at the same time as those used to treat CDI can reduce the effectiveness of the antibiotics used for CDI.

Guidelines from the Infectious Disease Society of American and The Society of Healthcare Epidemiologists of America, recommend the following antibiotics for the treatment of CDI:

First Occurrence

  • For an initial mild- to moderate episode, vancomycin 125 milligrams (mg) four times per day or fidaxomicin 200 mg twice per day for 10 days.
  • For a patient with severe CDI (white blood cell count greater than 15,000, or a serum creatinine great than 1.5 mg/dl, vancomycin 125 milligrams (mg) four times per day or fidaxomicin 200 mg twice per day for 10 days.
  • For patient with a fulminant CDI (hypertension or shock, intestinal obstruction, sepsis, or toxic megacolon), vancomycin 500 mg four times per day PLUS metronidazole 500 mg intravenously for 10 days.

Recurrent CDI

The following antibiotics are typically given for patients with a recurrent CDI:

  • For the first recurrence, the same antibiotics used for the first infection are usually given: vancomycin 125 milligrams (mg) four times per day or fidaxomicin 200 mg twice per day for 10 days.
  • For a second recurrence, the following treatments are recommended: Vancomycin by mouth taper or pulse 125 mg 4 times per day for 10 days, then rifaximin 400 mg 3 times per day for 20 days or fidaxomicin 200 mg 2 times per day for 10 days, or Fecal microbiota transplantation (see below).Note: Fidaxomicin is more expensive than vancomycin. Because of this, the insurance provider may only cover the cost of this antibiotic in certain circumstances (for example, if someone has recurrent CDI even after treatment vancomycin). If a patient has recurrent CDI, they should ask their doctor to see if fidaxomicin may be right for them.

Other Treatments

The following non-antibiotic options are available for the treatment of CDI:

  • Intravenous immunoglobulin (also called IVIG), a substance that contains antitoxins, has been used to treat some cases of CDI. However, this treatment has many side effects and may not be beneficial in adults, although there is some evidence that it is effective in children.
  • Bezlotoxumab is a human monoclonal antibody directed against C. difficile toxin B, which prevents intestinal damage and colitis. It is used in conjunction with antibiotics.
  • Fecal transplant, or fecal microbiota transplantation (FMT), is a process in which fecal matter, or stool sample, from a healthy donor is collected, strained, mixed with a sterile salt solution, and placed in a patient with CDI. This is usually performed by a process called colonoscopy, in which a flexible tube is passed thorough the anus and rectum. Several studies have shown that FMT is effective in treating patients with recurrent CDIs.
  • Another option is probiotics, which are live bacteria that do not cause disease but are capable of replacing the “good” bacteria that have been eliminated by antibiotics. Although a recent study has shown that use of probiotics in adults reduced the risk of CDI, additional data are needed before they can be recommended for CDI.
  • In patients with severe cases, surgery to remove the infected part of the colon might be required. The Centers for Disease Control and Prevention report that surgery is needed in only 1 or 2 of every 100 persons with a CDI.

What Treatment Options Are Expected in the Future?

Continued efforts are being made to develop new treatment options for CDI, including:

  • Narrow spectrum antibiotics, including ART24, DNV3837, and Ridinilazole, which are being studied to see how well they treat CDI, without further degrading the gut microbiome.
  • Microbiome-based therapies and products, which are distinct from antibiotics. Rather than trying to “kill” the C. diff bacteria, these therapies – similar to a fecal transplant – are geared to restoring the balance of the gut microbiome. Several companies are currently enrolling or have recently completed clinical trials, which show these therapies to be very promising. Among the therapeutics being developed are CP101, RBX2660SER-109, and VE303. Check out our Clinical Trials page for more information.
  • Vaccines and preventatives are being tested for their ability to prevent (rather than treat) CDI, including Pfizer’s Cover Trial and DAV132 from Da Volterra.Some of these new treatment options that are being tested will hopefully get approval from the US Food and Drug Administration (FDA) and will assist doctors in successfully preventing and treating CDIs, which can be quite devastating for both patients and their families.