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Best probiotics for irritable bowl syndrome (IBS)

For general information about probiotics and their use click here.

The list below is the result of experience and testing for treating IBS.  Please

contact me to find out which one is best for you.

It’s difficult for IBS researchers to pinpoint just how effective probiotics are.

This is due to differences in study design, patient populations, probiotics strains

and dosages used of previous clinical trials.

Generally speaking, there is emerging evidence that probiotics help to improve

overall symptom response and quality of life compared to taking a dummy pill

(placebo) over an 8-10-week period. This goes for all type of IBS (IBS-D, IBS-C, and

IBS-M).  However, they appear less effective for specifically treating abdominal

pain and bloating.

At the 2015 Yale University workshop, two particular probiotic varieties were

identified as the best options for IBS:

  • Bifantis (Bifidobacterium infantis 35624): a group of bacteria that normally live in the intestines, but specifically the strain 35624. It’s reported many people are missing this strain from their gut.

  • VSL#3: a probiotic mixture of eight strains (more on this below).

Given the majority of IBS patients experience diarrhoea as their main symptom (IBS-D), the majority of study subjects is no different.

For this reason, there is much more data on treating diarrhoea, and a general lack of recommendations for those struggling with constipation (IBS-C).


Fortunately, there has been a recent 90-day clinical trial on 122 patients with IBS-C. The researchers wanted to test the effects of two different probiotic mixtures versus a dummy pill (placebo).

The strains tested included:

  • Lactobacillus. acidophilus

  • Lactobacillus. reuteri

  • Lactobacillus. plantarum,

  • Lactobacillus. rhamnosus

  • Bifidobacterium. animalis subsp. lactis.


They found that between 66-90% of those taking either probiotic mixture responded very favourably to effects on bloating, abdominal pain and cramping, flatulence and constipation. By contrast, only 6-36% of the placebo group responded well.

Additionally, they found that beneficial effects were maintained 30 days after the last intake of probiotics. At least, after taking the probiotics for 60 days first.

From these data, it seems that probiotics containing at least a mixture of Lactobacilli species warrant consideration if you are having trouble with constipation.

Notably, the second mixture performed best overall and it contained both Lactobacillus plantarum and Bifidobacterium animalis. 

Which Probiotic Brands Are Best?

I realize that listing the best species is not so practical when it comes to purchasing an actual product.

So, these are the best probiotics for IBS currently available based on the current evidence and the opinion of gastrointestinal specialists. They are not listed in any particular order, and it’s currently not possible to recommend one over the other.

Dosage recommendations are listed on the product, but always speak to your healthcare professional before trying any new supplement.


This is one of the more well-known probiotic labels, highly regarded in the

medical community.

It’s also known as Vivomixx. VSL#3 was designed for patients with IBS,

ulcerative colitis or an ileal pouch.

It’s a high dose, high potency probiotic with multiple strains including:

  • Lactobacillus acidophilus

  • Lactobacillus plantarum

  • Lactobacillus casei

  • Lactobacillus delbrueckii subsp. Bulgaricus

  • Bifidobacterium infantis

  • Bifidobacterium longum

  • Bifidobacterium breve

  • Streptococcus salivarius subsp. thermophilus.

VSL#3 is well-studied and was used in many clinical trials. It has a strong and consistent track record for treating IBS symptoms in adults and children.

They also have a children’s variety available.


Symprove is a water-based probiotic mixture that contains:

  • Lactobacillus rhamnosus

  • Lactobacillus plantarum

  • Lactobacillus acidophilus

  • Enterococcus faecium.

A healthy gut contains a balance of each of these, but it’s likely an IBS gut does not.

The manufacturers claim it works better than other brands, and they tested Symprove against

7 other probiotic products in a laboratory experiment designed to mimic the environment the

probiotic would experience in the body. Based on these data it is superior because the bacteria

actually survive all the way to the gut, where they can then grow and make a difference.


For the record, VSL#3 was tested in this study and fared extremely well alongside Symprove.

The findings are very interesting, but keep in mind this was done in a laboratory and not actually measured inside a human or animal.

There is also one published 12-week clinical trial of Symprove in which 152 IBS patients completed the study.

Those taking the probiotic experienced a significantly greater reduction in symptom severity compared with the placebo group. This became very evident after the 4-week mark.

Four weeks after discontinuing treatment, the benefits largely disappeared. This suggests patients may requires ongoing treatment with Symprove.

For the record, Symprove is the most expensive of the three products listed in this article.

Alflorex and Align

This product is claimed to be the number 1 gastroenterologist recommended live culture in the US.

It’s called Alflorex in the UK and Align in the US (I’ll just refer to it as Alflorex here). Unlike VSL#3 and

Symprove, Alflorex is a single-species probiotic.

That is, it only contains Bifidobacterium infantis 35624 and nothing else. This is trademarked as 

Bifantis and was one of the top-rated probiotics in a Yale University workshop.  Notably it’s also

the most affordable of the three products listed.

As you’d expect there is a lot of research showing Alflorex has beneficial effects on gut health and bacteria, particularly in IBS patients.  Additionally, one of the latest probiotic review studies concluded that single species probiotics are most effective for improving overall IBS symptoms.

On the other hand, a very recent meta-analysis claimed Bifidobacterium infantis 35624 was largely ineffective for treating IBS. However, the authors appear to have mistakenly compared products with different Bifidobacterium species.  Oops!  As a result, a formal comment on this paper has recently been submitted that disputes those findings.

Note that Align was one of the eight products tested in the Symprove study mentioned above. They found it did not survive exposure to stomach acid and as a result did not grow to significant numbers in the gut.

This observation is clearly at odds with previous data from clinical trials, as well as the opinions of many researchers and gastrointestinal doctors. It’s likely their findings don’t paint the whole picture.

Honestly, I’m not quite sure what to make of it all but Alflorex is certainly worth a try if you have IBS.

It’s also available as a children’s drink and children’s straw, and appears safe for infants 


The Best Probiotics for IBS: A Double-Edged Sword

It certainly appears probiotics can help manage IBS, but only particular strains and mixtures.

Just keep in mind that they should not be used as a sole therapy.  In other words, probiotics are most effective in combination with current conventional treatments such as some medications (if recommended by your healthcare practitioner), and before or after a low FODMAP diet.

Also note that they can be a double-edged sword… what works great for some may only make symptoms worse in others. It very likely depends on your existing gut bacteria environment.

For this reason, you should be willing to experiment with different strains and different brands. Where one type doesn’t help, maybe another will do the job.

Bottom Line

The most clinically proven and recommended brands among gastrointestinal specialists are VSL#3, Symprove and Alflorex/Align, in no specific order. But as always, speak with your healthcare practitioner before trying anything new.

And last but not least: don't confuse probiotics with prebiotics!

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