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A specific blend of two probiotic strains may help reduce the duration of antibiotic-associated diarrhea

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4 Min read

Antibiotic-associated diarrhea (AAD) is thought to occur due to antibiotic-induced dysbiosis of the gut microbiome,1 i.e. the altered ratio of large taxa bacteria and decreased diversity.2 Clinical studies have demonstrated 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 severity and duration of AAD.3, 4


How to maintain healthy bowel habits:


Lactobacillus acidophilus,
LA-5® & Bifidobacterium, BB-12® 3
Potency: 4 billion CFU/day of each strain 3
Duration: Commence LA-5® & BB-12® the same day as starting the antibiotics, continue for a week longer than the antibiotics, consume the probiotic product a few hours after intake of antibiotics.3

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

Antibiotics frequently cause adverse gastrointestinal effects

Treatment with antibiotics commonly causes adverse gastrointestinal effects, ranging from mild and transient diarrhea to rare, life-threatening infections.6, 8 The effect is termed antibiotic-associated diarrhea and occurs when antibiotics induce dysbiosis in the intestinal tract, potentially causing harmful bacteria to multiply beyond their normal numbers.9 AAD is defined as diarrhea associated with antibiotic exposure, either while on antibiotics or for up to eight weeks after antibiotics have been discontinued. The symptoms of AAD include frequent watery bowel movements and crampy abdominal pain.10, 11

AAD is caused by changes in the composition and function of the intestinal microbiome.1

Microbial richness decreases with use of broad-spectrum antibiotics

The reduction in biomass and bacterial richness results in reduced competition for nutrients while also opening previously unavailable ecological niches. The consequence is that antibiotic-resistant species or opportunistic species with fast intrinsic growth rates, including pathogens such as Clostridium difficile, can repopulate and alter the ecological balance in the intestine (i.e. dysbiosis).13, 14, 15, 16, 17, 18 Additionally, the development and spread of microbial antibiotic resistance is a serious health concern given that previously effective antibiotics now fail.19

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Probiotics may help restore the microbiome and reduce the risk of AAD

The BB-12® and LA-5® probiotic strains have been studied in clinical trials and have demonstrated effectiveness at reducing the duration of AAD.3, 4 The two probiotic strains are thought to exert this beneficial effect by modifying dysbiosis through a bactericidal action, i.e. the probiotic bacteria compete with harmful bacteria by producing substances that are toxic for the pathogens.20, 21, 22 The BB-12® and LA-5® probiotic strains also help to improve the immune response by strengthening the Th1 response,23, 24 better enabling the body to combat new viral and bacterial infections.

A clinical trial demonstrated that BB-12® and LA-5® probiotic strains may reduce the duration of AAD

A randomized, double-blind, placebo-controlled, multicenter clinical trial investigated the effectiveness of LA-5® and BB-12® at preventing AAD.3 Adults recruited on to the study were prescribed a seven-day course of an oral antibiotic (either cefadroxil or amoxycillin) and supplemented with either placebo or the LA-5® and BB-12® probiotic blend (each at 4 million CFU/day). The intervention was initiated on the same day as the antibiotics, and lasted a further seven days after the course of antibiotics was completed.3 
AAD occurred in 10.8% of the probiotic group and 15.6% of the placebo group (p=0.19). Despite the incidence of AAD not being significantly different, the duration of the AAD was significantly shorter in the probiotic group compared to the placebo group (two days vs. four days, p=0.01).3
Additionally, a sub-group analysis of participants who reported AAD demonstrated that severe diarrhea (watery stools) occurred in 96% of the placebo group, compared to just 31.6% of the probiotics group (p<0.001).3

Management of AAD consists of supportive measures and discontinuation of antibiotics.7

Swimming in open sea during travel

Consider probiotic supplementation when treating with antibiotics

Antibiotic treatment disturbs the microbiome and can result in an overgrowth of 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 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

LA-5® and BB-12® are registered 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 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. Giannelli FR. Antibiotic-associated diarrhea. Journal of the American Academy of PAs. 2017;30(10):46-7. (PubMed

8. Coté GA, Buchman AL. Antibiotic-associated diarrhoea. Expert Opin Drug Saf. 2006;5(3):361-72. (PubMed

9. 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

10. 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

11. Alam S, Mushtaq M. Antibiotic associated diarrhea in children. Indian Pediatr. 2009;46(6):491-6. (PubMed

12. Koo H, et al. Individualized recovery of gut microbial strains post antibiotics. npj Biofilms and Microbiomes. 2019;5(1):30. (PubMed

13. Palleja A, et al. Recovery of gut microbiota of healthy adults following antibiotic exposure. Nat Microbiol. 2018;3(11):1255-65. (PubMed

14. De La Cochetiere MF, et al. Resilience of the dominant human fecal microbiota upon short-course antibiotic challenge. J Clin Microbiol. 2005;43(11):5588-92. (PubMed

15. Dethlefsen L, et al. The Pervasive Effects of an Antibiotic on the Human Gut Microbiota, as Revealed by Deep 16S rRNA Sequencing. PLoS Biol. 2008;6(11):e280. (PubMed

16. Jakobsson HE, et al. Short-term antibiotic treatment has differing long-term impacts on the human throat and gut microbiome. PLoS One. 2010;5(3):e9836. (PubMed

17. Jernberg C, et al. Long-term impacts of antibiotic exposure on the human intestinal microbiota. Microbiology. 2010;156(Pt 11):3216-23. (PubMed

18. Nasiri MJ, et al. Clostridioides (Clostridium) difficile infection in hospitalized patients with antibiotic-associated diarrhea: A systematic review and meta-analysis. Anaerobe. 2018;50:32-7. (PubMed

19. Sugden R, et al. Combatting antimicrobial resistance globally. Nature Microbiology. 2016;1(10):16187. (PubMed

20. 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

21. 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

22. 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

23. Lopez P, et al. Distinct Bifidobacterium strains drive different immune responses in vitro. Int J Food Microbiol. 2010;138(1-2):157-65. (PubMed

24. 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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