Taking Probiotics with Antibiotics – should I? And Why?

An antibiotic is something that kills micro-organisms, specifically bacteria.  When we have an infection that is caused by bacteria, doctors will often prescribe a course of antibiotics as the treatment.  The problem is that most them are not specific to a particular strain of disease causing bacteria and can therefore indiscriminately kill all bacteria in its path.

What's the problem with that I hear you ask.  Aren't all bacteria bad for us?

The answer to that is absolutely not.  There are a wide range that are hugely beneficial to us.  When you consider that our bodies contain 10 times more bacterial cells in them than human cells, you might get a sense for their importance.  Our gut is a prime example.  The bacteria we have in our gut have an important role – they are our first line of defence.  Check out the homepage for more details on the useful role bacteria play in the human body.

The word probiotics is the term we give to the beneficial bacteria in our gut. So what happens to the beneficial flora in our gut when we consume antibiotics?

The truth is that antibiotics can have a devastating effect on our good bacteria.  For this very reason, antibiotics really should be a last resort.  There are situations where they are necessary, so what can you do to protect your gut bacteria?

One therapy that should be considered is to take probiotics during the course of your antibiotics.  This may sound weird. I mean if antibiotics kill bacteria, surely they will kill the probiotics that are taken at the same time?  Several studies suggest that probiotics taken during a course of antibiotics can reduce the side effects of the antibiotics2, 5.

Probiotic Supplementation?

The bacteria in our gut comes from the food we eat.  Good nutrition can go a long way to good gut health, and that includes eating prebiotic foods that can help feed the good bacteria.  Fermented foods are a great way to get natural probiotics on the basis that they are fermented by bacteria.  The obvious ones are milk-based products like yogurt which can provide live Lactobacillus and Bifidobacteria cultures. Yoghurt also has a lot of other potential health benefits too.

If you can eat fermented foods on a regular basis, you may not need to take a probiotic supplement as these are effective in repopulating some of the good bacteria in your intestinal tract.  I've written an article on probiotic foods to help.  But what if you think you need a little extra help.  Are there any probiotic supplements that are worth considering?

If we think about human evolution, the bacteria that evolve to work well in our guts came from the foods we ate, and the soil that surrounded many of those foods as they grew.  I therefore personally prefer to take a soil based probiotic on the assumption that these bacteria are more likely to be the ones that are beneficial to our digestive systems.  A couple of studies 6,7 have shown it to be beneficial in treating the symptoms of irritable bowel syndrome.  To me, it just makes sense to me that a healthy gut flora will be made up of native soil-based bacteria.

Prescript Assist is a broad spectrum probiotic & prebiotic formula containing 29 strains of beneficial soil-based microorganisms (SBOs) in a prebiotic complex of humic and fulvic acids.  One benefit is that it does not need to be refrigerated and has been shown to have a shelf-life of at least 2 years  with only a 5% loss of viability over that period.

The complete list of SBOs in the formula is:


Each serving contains 620mg of this proprietary blend, and because the bacteria in the formula are all protected by a seed-like casing, they are better able to withstand the harsh stomach environment and make it into your intestines intact.

Whether you take a course of probiotics during your antibiotics is your choice.  However, if I ever have to take antibiotics myself, I'll always make sure I get good probiotics once my antibiotics are finished.  For me, that means a couple of weeks on Prescript Assist, while trying to eat as many fermented foods as I can.  That way I can make sure that my gut flora has a chance to recover from the devastating effects of the antibiotics.

Antibiotic associated diarrhea?

25 – 30% of patients taking antibiotics may suffer from antibiotic-associated diarrhea.  A number of clinical trials and research papers suggest that probiotics may help prevent the diarrhea3,4, however, it is not clear cut.  At least one large study  study looking at the effects Lactobacilli and bifidobacteria on antiobiotic-associated diarrhea showed no benefit with taking those probiotics1.  These two groups of bacteria are some of the more common strains used in over-the-counter probiotics.


  1. 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. http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(13)61 218-0/abstract
  2. Effect of probiotics on preventing disruption of the intestinal microflora following antibiotic therapy: A double-blind, placebo-controlled pilot study. http://www.sciencedirect.com/science/article/pii/S1567576905000482
  3. Probiotics in prevention of antibiotic associated diarrhoea: meta-analysis.  http://www.bmj.com/content/324/7350/1361.full
  4. Meta-analysis: the effect of probiotic administration on antibiotic-associated diarrhoea.  http://www.ncbi.nlm.nih.gov/pubmed/12182746
  5. The effect of oral administration of Lactobacillus GG on antibiotic-associated gastrointestinal side-effects during Helicobacter pylori eradication therapy.  http://www.ncbi.nlm.nih.gov/pubmed/11148433
  6. Prescript-assist probiotic-prebiotic treatment for irritable bowel syndrome: an open-label, partially controlled, 1-year extension of a previously published controlled clinical trial. http://www.ncbi.nlm.nih.gov/pubmed/17692729
  7. Prescript-Assist probiotic-prebiotic treatment for irritable bowel syndrome: a methodologically oriented, 2-week, randomized, placebo-controlled, double-blind clinical study. http://www.ncbi.nlm.nih.gov/pubmed/16117982

About Andy

Most people are totally unaware that millions of bugs exist in our gut. Even more people don't realize that these bugs are vital to our health and represent out first line of defense against disease. Andy Williams has a Ph.D. in animal physiology, and a strong interest in health & vitality. This site showcases one of his interest - the gut microbiome, and how it affects our health.

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