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Consuming a specific blend of two probiotic strains is associated with fewer and shorter cases of antibiotic-associated diarrhea

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4 Min read

Antibiotics are thought to disrupt the balance and diversity of the gut microbiome by eliminating not only the harmful, pathogenic bacteria but also some of the resident beneficial bacteria.1, 2 This often results in diarrhea, known as antibiotic-associated diarrhea (AAD). Clinical studies have shown that supplementation with a blend of the Lactobacillus acidophilus, LA-5® and Bifidobacterium, BB-12® probiotic strains (hereafter referred to by use of the trademarks LA-5® and BB-12®) may be effective at reducing the duration and severity of AAD.3, 4

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Antibiotics frequently affect the digestive system

Many different types of bacteria live in our gut and usually coexist harmoniously due to the many bacteria being optimally balanced. When in balance, the bacteria support our health. Antibiotics often disrupt this balance, which can potentially enable harmful bacteria to multiply beyond their normal numbers,7 altering how the digestive system functions. This is why treatment with antibiotics often causes mild and temporary diarrhea known as antibiotic-associated diarrhea.6, 8 
AAD can occur not only while taking a course of antibiotics but also for up to eight weeks after the course of antibiotics has finished. Symptoms of AAD typically include frequent episodes of loose and watery bowel movements, and crampy abdominal pain.9, 10 

AAD is a benign and self-limiting diarrhea that may occur with the use of antibiotics.5, 6

Probiotics may help restore balance to the microbiome, reducing the risk of AAD 

The BB-12® and LA-5® probiotic strains have been investigated in clinical studies and have been associated with reducing the duration of AAD.3, 4 The two probiotic strains are thought to bring about beneficial effects by producing substances that are toxic for harmful bacteria.11, 12, 13 The BB-12® and LA-5® probiotic strains also help improve the immune system by strengthening our immune response,14, 15 better enabling the body to combat new viral and bacterial infections.
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BB-12® and LA-5® probiotic strains may reduce the duration of AAD 

A high-quality clinical study investigated the effectiveness of the LA-5® and BB-12® probiotic strains at reducing the risk and severity of AAD.3 All participants were given a seven-day course of an oral antibiotic. On the same day that the antibiotics course started, half of the participants were given a placebo and the other half were given a blend of the LA-5® and BB-12® probiotic strains. Participants continued with the placebo or probiotic blend for a further seven days after the course of antibiotics was completed.3 
Only 10.8% of the probiotic group experienced AAD, compared to 15.6% of the placebo group. Further, the duration of the AAD was significantly shorter in the probiotic group (two days) compared to the group who took a placebo (four days).3
Of those participants who did experience AAD, severe diarrhea occurred in 96% of the placebo group, compared to just 31.6% of the probiotics group.3  


Antibiotics disrupt the balance of bacteria in the gut microbiome, often resulting in AAD.1

Ask your doctor about probiotics when being treated with antibiotics

Antibiotic treatment disrupts the balance of the gut microbiome and can result in an overgrowth of harmful, pathogenic bacteria. This often results in the development of antibiotic-associated diarrhea. Clinical studies suggest that supplementing with the BB-12® and LA-5® probiotic strains may help reduce the duration and severity of AAD.3, 4
To read more about Chr. Hansen probiotic strains and reducing the risk of diarrhea in children, click here.

CFU: Colony Forming Unit

BB-12® and LA-5® are trademarks of Chr. Hansen A/S.

The article is provided for informational purposes regarding probiotics and is not meant to suggest that any substance referenced in the article is intended to diagnose, cure, mitigate, treat, or prevent any disease.
Bifidobacterium, BB-12® 

The probiotic strain Bifidobacterium, BB-12® is the world’s most documented probiotic bifidobacterium. It has been extensively studied and has been associated with improved outcomes across various health areas.

BB-12® is a registered trademark of Chr. Hansen A/S

BB-12 consumer logo TM
Lactobacillus acidophilus, LA-5®

The probiotic strain Lactobacillus acidophilus, LA-5® has demonstrated benefits, for example, in gastrointestinal health when used in combination with Bifidobacterium, BB-12®.

LA-5® and BB-12® are trademarks of Chr. Hansen A/S


References Open Close

1. Francino MP. Antibiotics and the Human Gut Microbiome: Dysbioses and Accumulation of Resistances. Front Microbiol. 2016;6:1543-. (PubMed)
2. Walker WA. The importance of appropriate initial bacterial colonization of the intestine in newborn, child, and adult health. Pediatr Res. 2017;82(3):387-95. (PubMed)
3. Chatterjee S, et al. Randomised placebo-controlled double blind multicentric trial on efficacy and safety of Lactobacillus acidophilus LA-5 and Bifidobacterium BB-12 for prevention of antibiotic-associated diarrhoea. J Assoc Physicians India. 2013;61(10):708-12. (PubMed)
4. de Vrese M, et al. Probiotic lactobacilli and bifidobacteria in a fermented milk product with added fruit preparation reduce antibiotic associated diarrhea and Helicobacter pylori activity. J Dairy Res. 2011;78(4):396-403. (PubMed)
5. Szajewska H, et al. Probiotics in the prevention of antibiotic-associated diarrhea in children: a meta-analysis of randomized controlled trials. J Pediatr. 2006;149(3):367-72. (PubMed)
6. Allen SJ, et al. Lactobacilli and bifidobacteria in the prevention of antibiotic-associated diarrhoea and Clostridium difficile diarrhoea in older inpatients (PLACIDE): a randomised, double-blind, placebo-controlled, multicentre trial. Lancet. 2013;382(9900):1249-57. (PubMed)
7. Agamennone V, et al. A practical guide for probiotics applied to the case of antibiotic-associated diarrhea in The Netherlands. BMC Gastroenterol. 2018;18(1):103. (PubMed)
8. Coté GA, Buchman AL. Antibiotic-associated diarrhoea. Expert Opin Drug Saf. 2006;5(3):361-72. (PubMed)
9. McFarland LV, Goh S. Preventing pediatric antibiotic-associated diarrhea and Clostridium difficile infections with probiotics: a meta-analysis. World Journal of Meta-Analysis. 2013;1(3):102-20. (Source)
10. Alam S, Mushtaq M. Antibiotic associated diarrhea in children. Indian Pediatr. 2009;46(6):491-6. (PubMed)
11. Martins FS, et al. Comparative study of Bifidobacterium animalis, Escherichia coli, Lactobacillus casei and Saccharomyces boulardii probiotic properties. Arch Microbiol. 2009;191(8):623-30. (PubMed)
12. Fooks LJ, Gibson GR. Mixed culture fermentation studies on the effects of synbiotics on the human intestinal pathogens Campylobacter jejuni and Escherichia coli. Anaerobe. 2003;9(5):231-42. (PubMed)
13. Tabasco R, et al. Lactobacillus acidophilus La-5 increases lactacin B production when it senses live target bacteria. Int J Food Microbiol. 2009;132(2-3):109-16. (PubMed)
14. Lopez P, et al. Distinct Bifidobacterium strains drive different immune responses in vitro. Int J Food Microbiol. 2010;138(1-2):157-65. (PubMed)
15. Sheikhi A, et al. Probiotic Yogurt Culture Bifidobacterium Animalis Subsp. Lactis BB-12 and Lactobacillus Acidophilus LA-5 Modulate the Cytokine Secretion by Peripheral Blood Mononuclear Cells from Patients with Ulcerative Colitis. Drug Res (Stuttg). 2016;66(6):300-5. (PubMed

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