Probiotics and Prebiotics

Publication Date: March 1, 2023


Genera, species, and strains used as probiotics

The term “probiotic” should be reserved for live microbes that have been shown in controlled human studies to impart a health benefit.
Probiotic manufacturers should register their strains with an international depository.
Recommendations of probiotics, especially in a clinical setting, should tie specific strains to the claimed benefits based on human studies.

Products: dosages and quality

From a scientific perspective, a suitable description of a probiotic product as reflected on the label should include:
  • Genus and species identification, with nomenclature consistent with current scientifically recognized names
  • Strain designation
  • Viable count of each strain at the end of shelf-life
  • Recommended storage conditions
  • Safety under the conditions of recommended use
  • Recommended dose, which should be based on induction of the claimed physiological effect
  • An accurate description of the physiological effect, as far as is allowable by law
  • Contact information for post-market surveillance
The dosage should be based on human studies showing a health benefit.
Microbiological quality standards should meet the needs of at-risk patients.

Clinical applications

Colorectal cancer prevention

Although diet is thought to contribute to the onset of colorectal cancer, and both probiotics and prebiotics have been shown to improve biomarkers associated with colorectal cancer, there are limited data in humans showing any benefit of probiotics or prebiotics in the prevention of colorectal cancer.

Diarrhea treatment and prevention

Treatment of acute diarrhea
Some probiotic strains are useful in reducing the severity and duration of acute infectious diarrhea in children. Oral administration shortens the duration of acute diarrheal illness in children by approximately 1 day. Several meta-analyses of controlled clinical trials testing other probiotic strains have been published that show consistent results suggesting that probiotics are likely to be safe and effective. However, the mechanisms of action may be strain-specific.
Prevention of acute diarrhea
In the prevention of adult and childhood diarrhea, there is evidence that certain probiotics can be effective in some specific settings.
Prevention of antibiotic-associated diarrhea
In the prevention of antibiotic-associated diarrhea, there is strong evidence of efficacy in adults or children who are receiving antibiotic therapy.
Prevention of Clostridium difficile diarrhea
A 2016 meta-analysis concluded that probiotics can reduce the risk of developing C. difficile–associated diarrhea in patients receiving antibiotics. However, the authors caution that additional studies are needed in order to determine the best dosage and strain.
Prevention of radiation-induced diarrhea
The gut microbiota may play an important role in radiation-induced diarrhea by reinforcing intestinal barrier function, improving innate immunity, and stimulating intestinal repair mechanisms. A 2013 meta-analysis concluded that probiotics may be beneficial in the prevention and possibly in the treatment of radiation-induced diarrhea.

Helicobacter pylori eradication

The 2016 Maastricht V/Florence Consensus Report on management of H. pylori infection concluded that probiotics and prebiotics show promise in reducing side effects of treatment for H. pylori. However, the quality of the evidence and the grade of recommendation were low. A 2014 meta-analysis of randomized trials suggests that supplementation of anti–H. pylori antibiotic regimens with certain probiotics may also be effective in increasing eradication rates and may be considered helpful for patients with eradication failure. There is no evidence to support the concept that a probiotic alone, without concomitant antibiotic therapy, would be effective.

Hepatic encephalopathy prevention and treatment

Prebiotics such as lactulose are commonly used for the prevention and treatment of hepatic encephalopathy. Evidence for one probiotic mixture suggests that it can reverse minimal hepatic encephalopathy.

Immune response

There is suggestive evidence that several probiotic strains and the prebiotic oligofructose are useful in improving the immune response. Evidence suggestive of enhanced immune responses has been obtained in studies aimed at preventing acute infectious disease (nosocomial diarrhea in children, influenza episodes in winter) and studies that tested antibody responses to vaccines.

Inflammatory bowel disease (IBD)

There is good evidence for the usefulness of certain probiotics in preventing an initial attack of pouchitis, and in preventing further relapse of pouchitis after the induction of remission with antibiotics. Probiotics can be recommended to patients with pouchitis of mild activity, or as maintenance therapy for those in remission.
Ulcerative colitis
Certain probiotics have been found to be safe and as effective as conventional therapy in achieving higher response and remission rates in mild to moderately active ulcerative colitis in both adult and pediatric populations.
Crohn’s disease
Studies of probiotics in Crohn’s disease have indicated that there is no evidence to suggest that probiotics are beneficial for maintenance of remission of Crohn’s disease.

Irritable bowel syndrome (IBS)

A reduction in abdominal bloating and flatulence as a result of probiotic treatments is a consistent finding in published studies; some strains may ameliorate pain and provide global relief. The literature suggests that certain probiotics may alleviate symptoms and improve the quality of life in patients with functional abdominal pain.


Certain probiotic strains have been shown to reduce crying time in breastfed infants with colic.

Lactose malabsorption

Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus improve lactose digestion and reduce symptoms related to lactose intolerance. This was confirmed in a number of controlled studies with individuals consuming yogurt with live cultures.

Necrotizing enterocolitis

Probiotic supplementation reduces the risk of necrotizing enterocolitis in preterm neonates. Meta-analyses of randomized controlled trials have also shown a reduced risk of death in probiotic-treated groups, although not all probiotic preparations tested are effective. The number needed to treat to prevent one death from all causes by treatment with probiotics is 20.

Nonalcoholic fatty liver disease

The usefulness of certain probiotics as a treatment option to mitigate steatohepatitis has been proven through a number of randomized clinical trials in adults and children. Probiotics provided improvements in the outcomes of homeostasis model of assessment (HOMA) scores, blood cholesterol, tumor necrosis factor-α (TNF-α), and liver function tests—alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Further studies are needed to confirm long-term benefits.

Prevention of systemic infections

There is insufficient evidence to support the use of probiotics and synbiotics in critically ill adult patients in intensive-care units.

Recommendation Grading




Probiotics and Prebiotics

Authoring Organization

Publication Month/Year

March 1, 2023

Supplemental Implementation Tools

Document Type


External Publication Status


Country of Publication


Inclusion Criteria

Male, Female, Adolescent, Adult, Older adult

Health Care Settings


Intended Users

Healthcare business administration, nurse, nurse practitioner, physician, physician assistant


Assessment and screening, Treatment, Management

Diseases/Conditions (MeSH)

D019936 - Probiotics, D056692 - Prebiotics


Probiotics , Prebiotics, Lactobacillus, live microorganism