Probiotic Treatment For Blastocystis Hominis

byron bay australia herbal medicine functional medicine naturopath

Blastocystis hominis is, and always will be a subject of interest for me. Acute infection with this little protozoan bug, along with bacterial infections was my first experience with ongoing sub-par health. For an introduction to this parasite see here

Since writing this article I have had success treating my Blastocystis hominis parasite infection.

Over the years my thinking around treatment ideas have changed. Originally it went something like this

  1. Find the bug
  2. Kill the bug using antimicrobial herbs
  3. Rebuild the gut integrity and microflora

While this may seem overly simplistic to anyone who has done antibiotics and only felt worse it is the general approach of many practitioners, including functional medicine, naturopaths and herbalists. Delving into the complexity of the human body and the intricacies of our gut microbiome it became clearer and clearer that the approach of “find and kill” can lead some unfortunate people down the path of diminishing returns, not to mention diminishing gut flora.

Recently I came across a paper looking into the use of one particular and well researched probiotic in the treatment of Blastocystis hominis in children displaying symptoms including

  • Abdominal pain
  • Diarrhea
  • Nausea
  • Vomiting
  • Flatulence

The randomised, single blinded control trial compared Saccharomyces cerevisiae var. boulardii CNCM I-745 to the standard treatment, an antibiotic called metronidazole, and a third group with no treatment at all. The treatment intervention lasted for 10 days.


Probiotic Treatment for Blastocystis – Results After 15 Days

After 15 days taking a probiotic to treat Blastocystis hominis infections there were some surprising and exciting results.

The probiotic group experienced 77.7% clinical cure rate – this is based on the symptoms of the patients and not on stool analysis to confirm eradication of the parasite. Analysing the stool found that only 72.2% had cleared the parasite.

The antibiotic group experienced 66.6% clinical cure rate (based on symptoms and not stool analysis). Interestingly when analysing the stool the antibiotic group achieved a 80% clearance rate at 15 days. This is telling us that when patients took the antibiotics they cleared the parasite (80% of them) but many didn’t actually feel better (13.4% still had gut symptoms!)

The control group, receiving no treatment experienced only 40% clinical cure rate and 26.6% stool analysis clearance rate. While parasites such as Blastocystis can stick around and cause troubles for years there are some people that can naturally clear the infection. It could be that there immune system is more finely tuned to deal with these bugs.


Probiotic Treatment for Blastocystis – Results After 30 Days

Checking in at day 30 the results were very interesting.

The group of people that were taking the probiotic to treat Blastocystis hominis found

  • 94.4% – cure rate based on symptoms. Meaning that 94.4% of the people taking the probiotic felt better and no longer had any gut symptoms.
  • 94.4% – based on stool analysis. Meaning that 94.4% of the people no longer had evidence of Blastocystis in their stool.

The antibiotic group

  • 73.3% based on symptoms. This is quite a bit lower than the probiotic group, all based in the symptoms reported from the patient. And remember that’s what it is all about. How is the person feeling? Do they still have symptoms?
  • 93.3% based on stool analysis (interesting spread here). Again meaning that more people had reportedly cleared the Blastocystis infection but didn’t actually feel better.

The control group was treated with the antibiotic after day 15 so there was no data for them at day 30.


Assessing The Cure Rate For Blastocystis

It is worth noting that the trial seemed to screen for Blastocystis just one time when assessing the cure rates and this particular parasite has random shedding habits. Many clinicians that are familiar with Blastocystis recommend three separate stool samples on different days to assess infection.

The other very important point that very few people are talking about is the importance of the particular strain of probiotic used. Many will assume that because this particular strain of Saccharomyces cerevisiae var. Boulardii, the CNCM I-745 aka biocodex strain is helpful in the treatment of Blastocystis hominis that all strains of Saccharomyces cerevisiae var. Boulardii will be helpful. This is incorrect and research has looked into the differences displayed between different strains in the same species of probiotics.

Dr. Jason Hawrelak is the best source to dig into if you are interested in this subject. In a lecture he used the example of E. coli when talking about strain specificity. Some strains of E. coli are members of healthy flora and some can contribute to a wide range of symptoms including urinary tract infections.


More On The Probiotic Saccharomyces boulardii

The Therapeutic Advances in Gastroenterology published an interesting review on Saccharomyces boulardii in 2011 looking at some promising research done on the yeast in regards to a range of different chronic and acute diseases including

  • Antibiotic-associated diarrhea
  • Clostridium difficile infection
  • Acute diarrhea
  • Persistent diarrhea
  • Enteral nutrition-related diarrhea
  • Traveler’s diarrhea
  • Helicobacter pylori infection
  • Chronic diseases
  • Crohn’s disease
  • Ulcerative colitis
  • Irritable bowel syndrome
  • Parasitic infections
  • Amebic colitis
  • Giardiasis
  • Blastocystis hominis
  • Human immunodeficiency virus (HIV)-related diarrhea

While digging into each and every point they covered is beyond this article it is worth noting a few key points found in the literature on the use of Saccharomyces boulardii.

  1. It has the ability to reach the colon intact (although in reduced numbers)
  2. Has the ability to survive the body temperatures (rare for yeasts)
  3. Is naturally resistant to antibiotics, leading to recommendations for supplementing while taking antibiotics or even antimicrobial herbs

Unfortunately at the moment the biocodex strain of Saccharomyces boulardii (CNCM I-745) isn’t available in Australia but it could be worth looking into international shipping options until it is. Alternatively there are a number of Saccharomyces boulardii strains on the Australian market that may possibly have similar effects. The problem here is that there is no solid data to backup the available strains and it results in a ‘try and see’ approach.


Closing Thoughts. Can Probiotics Cure Parasite Infections?

This is the million dollar question. Can probiotics cure parasite infections.

It isn’t a clear yes or no answer.

Since writing this article I have been contacted by a number of different people looking for more information on the use of probiotics in gut infections. As my understanding on the complexity of the gut ecosystem has evolved I now look at the use of probiotics as just one of many approaches to treating gut infections, parasites and bacterial dysbiosis.

A balanced approach of nurturing the gut with prebiotics and probiotics and intervening with well chose herbal antimicrobials appears to have the most success, is best tolerated and minimised damage to the gut microbiome. All good things. For a general overview on the different approaches see – Gut Infections And How To Deal With Them

Now I would like to hear from you. Have you had any experiences with probiotics to help with your health concerns? Share your thoughts below.


References and Resources

  1. Blastocystis hominis – A Protozoan Gut Parasite
  2. Clinical efficacy of Saccharomyces boulardii or metronidazole in symptomatic children with Blastocystis hominis infection.
  3. Dr. Jason Hawrelak
  4. Efficacy and safety of the probiotic Saccharomyces boulardii for the prevention and therapy of gastrointestinal disorders

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  1. Hi Todd, thanks for your articles. I’m interested to know what strains you’re referring to in your statement “alternatively there are a number of Saccharomyces boulardii strains on the Australian market that may possibly have similar effects.”

    I’m in Brisbane and I’ve just finished a 10 day course of 3 antibiotics after I became impatient with the lack of success on natural antiparasitic meds for blasto. I’m feeling skeptical the antibiotics have worked, so I’m researching alternative treatments while i wait to test for blasto again.

    I’m also curious as to how your treatment for blasto is progressing. Have you had any luck?

    1. No problem at all. There are a number of available strains. Metagenics does one as does bioceuticals. You can also source them through Iherb from overseas. I have just heard from a company importing the strain referenced above – they are calling their product Yomogi (I’ll update the blog post asap!)
      Unfortunately after a few rounds of antimicrobials I still have blastocystis. I keep feeling like I’ve kicked it, then retest and it’s still there. The herbal antimicrobials have definitely helped immensely and have improved my symptoms in a big way! Still working out the best way forward. It’s a tough one to eliminate.

      1. Great, thanks for the info. There is a compounding chemist in Brisbane who stocks the Yomogi. I’ll look into it.

        Sorry to hear about your lack of success with kicking blasto. It’s such a bugger of a thing! I wish you all the best.

        1. Thanks Gita! Learning lots of life/health lessons with this bug. Still I’ll be over the moon when it’s finally gone!

      2. Hi Todd, I have been trying to find the strain they used in this study Saccharomyces cerevisiae var. boulardii CNCM I-745 in Australia. When I researched the Yomogi website the strain they use is Saccharomyces cerevisiae var boulardii Hansen CBS 5926 have they renamed it or is this not the same strain?

        1. yes apparently they are the same strain. I will be updating this blog article with the research papers that support this claim in the next week.

  2. Hey Todd,
    Any updates as to your recovery? I’ve had BH for 4 months and have also tried many things but still have it. I just purchased the Saccharomyces boulardii today (product name Floristor here in Canada). Praying it will work for me!

    1. Its a tough one to treat. I’ve come to look at the boulardii probiotic as an add on to other antimicrobial herbs, not so much a stand-alone treatment. Still worth a try, as it can help generally.

  3. Can i add here that it is important to NOT take general probiotics while you have Blasto. Blasto feeds on both good and bad so it is best to avoid until after it has been cleared.
    S.bouldarii is the only exception. The dosage for adults should be 500mg (2 caps twice or 3 times per day for at least 2 weeks)1
    It has also been said that antioxidants hinder the elimination of blasto.
    I had success using serrapeptase, pomegranate husk and seed as well as a liver refresh from iherb.

    Unfortunatly i became reinfected so starting the long painful journey again.

    1. very interesting info. I have been reading quite a bit on the pomegranate husk as an effective antimicrobial (did you find a good product?) but haven’t come across blastocystis feeding on the gut microflora.
      Good to hear that the biofilm (serrapeptase) was helpful in your treatment.
      What was the liver refresh product if you don’t mind sharing? I have noticed a number of elevated liver enzymes in people with chronic/long term blasto infection, it seems like a likely correlation.
      Thanks for sharing it greatly helps!

    1. If they haven’t advertised the specific strain I would say not. That doesn’t mean that it isn’t helpful it just means that the effects are still unconfirmed. There are two different camps in probiotic research. One that says strain specificity is of utmost importance and the other that disagrees. If you feel like it’s helping then go for it!

    1. This is the big question. Some would say no and cite the huge percentage of asymtomatic people with blastocystis infection (this tends to be the stronger arguement). Others would encourage treatment and are concerned with the possible detrimental effects that blastocystis has even in asymptomatic people. Personally I haven’t made my mind up. Seeing as it is quite difficult to treat (generally speaking) I might lean towards not going on a full eradication program. I might change that opinion down the line though. Sorry for the long winded answer!

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