Gut Health

Why should you take probiotics while on antibiotics?


Women drinking water

Who hasn't taken antibiotics at least once in their life? In 2019 alone in Canada, 207.6 million daily doses were dispensed by community pharmacies and 16.4 million by hospitals, according to a report from the Public Health Agency of Canada.

While antibiotics are an important part of medicine, their overuse and misuse is a concern to health authorities. Not only does this harm vulnerable patients, but it also contributes to increased antibiotic resistance worldwide.

How antibiotics work

There are two main ways in which antibiotics work:

  • they prevent the growth and proliferation of bacteria
  • they kill bacteria.

While antibiotics attack the "bad" bacteria that cause an infection, they also harm innocent victims: the "good" microorganisms also die.

Common side effects of antibiotics treatment

About one in five people experience side effects when taking diarrhea, constipation, bloating, abdominal pain, etc. 

Here's how it works. To perform its functions and protect us, the intestinal microbiota must be composed of a large number of different species. Their number and diversity are essential to our health. Antibiotics disturb the microbiota! They reduce the number of bacterial species and are associated with the presence of antibiotic resistance genes. These disturbances can last for months or even years after an antibiotic treatment.

Figure 2: Following antibiotics, there is an imbalance in the diversity bacteria in the gut, with an increase in harmful bacteria

In the short term, antibiotics reduce our army of good bacteria. As a result, the mucus layer that helps protect the intestinal wall becomes thinner and the junctions between cells loosen. In other words, antibiotics weaken the intestinal wall. This results in diarrhea until 35% of cases in children, and until 39% in adults. Antibiotic-associated diarrhea (AAD) can occur during treatment and up to 8 weeks after treatment is stopped.

It varies according to age, individual susceptibility, and antibiotic category:

Preventing or reducing adverse effects is possible

Several scientific studies have shown that specific strains of probiotics help limit the damage caused by antibiotics. They help fight pathogenic bacteria and promote a good immune response.

Since probiotics composed of bacteria are likely to be killed by antibiotics, it is beneficial to choose probiotics composed of yeast. Florastor is the only probiotic supplement containing the yeast Saccharomyces boulardii CNCMI-745, a strain naturally resistant to all antibiotics. This means that you can consume our probiotics without having to worry about taking antibiotics 2-3 hours apart (minimum).

Saccharomyces boulardii CNCMI-745 has been researched worldwide for over 65 years. Florastor probiotic supplements have been studied in over 100 clinical trials and have been used for 65 years. Florastor reduces the incidence of antibiotic-associated diarrhea by up to 80% in children and up to 84% in adults.

It promotes the balance of the intestinal microbiota and strengthens the immune system. Saccharomyces boulardii CNCM I-745 has been recommended by : 

  • The Canadian Digestive Health Foundation (CDHF)
  • The World Gastroenterology Organization (WGO)
  • The European Society for Paediatric Gastroenterology Hepatology and Nutrition (ESPGHAN)

It's hard enough to fight off infections without suffering adverse effects from antibiotic treatment. Probiotic supplements such as Florastor are our allies.

Stéphanie Côté,


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