Probiotics: Do They Work Best On Their Own Or In Conjunction? - Dr. Michael Ruscio, DC

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Probiotics: Do They Work Best On Their Own Or In Conjunction?

Surprising findings about combining probiotics with antihistamines or antimicrobials and the relationships between probiotic supplementation, depression, SIBO, IBS, and allergies.

Are two therapies better than one? The latest probiotics research covers a wide range of health conditions, from SIBO to psoriasis, and shows the outcomes of combining probiotics with other therapies like antimicrobials and antihistamines. Listen to the podcast to learn more about what may be beneficial for treating symptoms of depression, allergic rhinitis, IBS, SIBO, asthma, and other health conditions.

In This Episode

Intro… 00:08
Probiotics and symbiotics for depression… 00:44
Probiotics for pre-term neonates… 03:39
Probiotics in pregnancy… 05:30
Bifidobacterium probiotics for diarrhea in those with IBS… 06:58
The effect of E Coli nissle 1917 on hepatic encephalopathy 08:13
Saccharomyces boulardii with triple therapy for H pylori… 12:22
Probiotics for the treatment of allergies… 17:53
Probiotics as an adjunctive therapy for hives… 20:56
Psoriasis treated via oral probiotics… 22:59
Probiotic-assisted eradication of H Pylori CagA… 24:08
Probiotics for COVID 19… 26:23
Probiotics for Necrotizing enterocolitis in infants… 27:48
Bifidobacterium animalis for gastrointestinal symptoms… 29:15
If you need help… 30:21
Outro… 35:23

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➕ Full Podcast Transcript


Welcome to Dr. Ruscio, DC radio, providing practical and science-based solutions to feeling your best. To stay up to date on the latest topics, as well as all of our prior episodes, make sure to subscribe in your podcast player. For weekly updates, visit That’s The following discussion is for educational purposes only and is not intended to diagnose or treat any disease. Please do not apply any of this information without first speaking with your doctor. Now let’s head to the show.

Dr Rusico:

Hey, everyone. Welcome back to Dr. Ruscio, DC radio. This is Dr Michael Ruscio, DC and let’s do more on probiotics. Boy. There is always so much interesting research here to share. The first study looked at the gut microbiome in patients with depression and what benefits could be conferred by prebiotics, probiotics, or symbiotics (the combination of prebiotics and probiotics). This was a systematic review of clinical trials and observational trials, 43 studies with just under 4,000 participants with depression. And here’s what they found: probiotics and symbiotics (again a combination of probiotics plus prebiotics) led to improvements in depressive symptoms. Whereas prebiotics alone had no effect. This shouldn’t be surprising. We’ve talked about a number of studies, in fact meta-analyses at this point, that have found that probiotics can improve depression through this likely in part gut-brain connection.

Dr Ruscio, DC:

The evidence for prebiotics is not as strong in a multitude of areas, although there is benefit demonstrated from either a higher probiotic diet or from supplementation. But it’s really important for us to keep reiterating that if you go do the direct-to-consumer stool test and they say, “oh, you have low diversity, take prebiotics and eat a high prebiotic diet,” for some, yes, it will help, but you may be one of the many patients who end up at our clinic saying “I did insert-heavily-marketed-test-here and followed the recommendations and it got worse.” And that’s because your gut is not a simple one input for one output, take prebiotics, increase diversity, feel better. It’s not that easy. There is this relationship between your gut and the immune system that houses the bacteria in your gut. And also probably most important to mention, amidst a few counterarguments here, but that most of these tests, pretty much all of them are quantifying what’s going on in the colon.

Dr Ruscio, DC:

And the small intestine is where 90% of calories are absorbed [and] most nutrients are absorbed. And because of that, it’s this delicate selective membrane. That’s also most amenable to leaky gut. So if you’re making your decisions around the colon and forgetting the small intestine, this is likely why a fair amount of treatment of the labs doesn’t work. Because the labs have limitations and most of the labs are quantifying things that go on in the colon or the large intestine.

Dr Ruscio, DC:

The next study looked at probiotics and how they impact sepsis in pre-term neonates. This was a systematic review looking at about 1500 studies on probiotics in pre-term infants and sepsis was caused by probiotics in 25 cases. So this is important to keep in mind, and this could be one data point that your OB or whomever is referring to when they say, “well, don’t give your child probiotics, that could cause sepsis.”

Dr Ruscio, DC:

Now, as we’ve discussed, there’s also other data showing that probiotic supplementations improve infection rate outcomes, I believe also growth, and reduce necrotizing enterocolitis in pre-term infants. So very important to have a meta view on your healthcare decisions and not cherry pick one study. And also in your hospitalist or conventional medical provider’s defense, they may have been served this up, so to speak, from an anti-natural medicine newsletter that they’re part of or… You know what happens here, right? The one study that’s most novel or new or different is the one that gets all the press. And again, this is why I think it’s so important what we’re doing here on the podcast, as I pat myself on the back, trying to share the research here, both sides and help you see the meta view. So the risk to reward ratio regarding probiotics with pre-term infants seems to be strongly toward the side of an overall benefit.

Dr Ruscio, DC:

Okay. The next study, looking at probiotics in pregnancy, and if they reduce allergy and asthma in the infants and the children. [It is] a systematic review of six studies and they found that probiotics that were taken during pregnancy led to no change in atopic conditions in two of the studies. Atopic is just a general term for skin pimples, lesions. So two of six studies found no effect. There was less atopic conditions in two studies and less atopic conditions in a subset of children in one of six studies. So what we’re seeing here is inconsistent results regarding if taking a probiotic while breastfeeding/nursing will improve skin conditions in your child. Although, given the fact that there are a few different benefits that have been demonstrated at least to a greater extent, then I still think it’s in the favor of the parents to consider using probiotics during that time. But it’s also important to mention that they are not a cure-all. So they can help, but very few things will help everything all of the time. In fact, if anyone tells you that I would be very cautious about whatever they’re recommending.

Dr Ruscio, DC:

Okay. Another study looking at if a certain bifidobacterium probiotic can improve diarrhea in those with IBS. And they looked at 21 IBS patients, they were all treated with probiotics, and actually 16 of these 21 were also diagnosed with SIBO. And remember that if you give someone with SIBO a probiotic, they will spontaneously combust and it will not be good. So be very careful. After one month, the probiotic group led to improved IBS symptoms, including less abdominal pain, less extension, less diarrhea, less urgency, a better feeling of complete evacuation, less depression, actually a very strong impact on depression. One of the strongest findings was on depression. And SIBO was eradicated in 25% of the cases. But remember, you should never give someone with SIBO probiotics. Or you should only give someone the very special probiotic that I went to a weekend seminar and the guy on this stage told me this is the special one for SIBO because science. Okay.

Dr Ruscio, DC:

So moving along the next study, the effect of E coli nissle 1917 on hepatic encephalopathy. Now remember hepatic encephalopathy, I’ve discussed this before. It’s a good model showing us the connection between the gut, liver, and toxins and the brain. And in this condition of hepatic encephalopathy, the liver is burdened, diseased, dysfunctional. It cannot adequately perform it’s job of essentially filtration, detoxification. Toxins build up in the blood, things that go into the blood eventually make their way across the blood-brain barrier into the brain, and then toxins and other particles that should have been filtered start triggering inflammation in the brain.

Dr Ruscio, DC:

And this leads to MCI (mild cognitive impairment) amongst a few other cognitive symptoms that have been identified. And we’ve discussed in the past that Rifaximin has been documented to improve, and I believe there’s even perhaps a meta-analysis showing that Rifaximin is an effective treatment for hepatic encephalopathy, and it’s probably because it has this impact on the gut and namely this antibacterial impact on SIBO. And guess what else does? Probiotics. But there’s been a posse of data showing this medical condition could benefit from probiotics. Although I had a very strong suspicion and I’ve speculated in the past that it would, that probiotics would. So this was an open label study—caution there, open label is definitely amenable to placebo—small study, 45 patients. They were randomized to Lactulose, Rifaximin, or E coli nissile 1917. E coli nissile 1917 is not available in the United States because, to my understanding, regulators say E coli bad. Doesn’t matter what kind of E coli it is, even one that has, there’s gotta be over 20 studies on E coli nissile 1917, but because the E coli 0157, the one that caused the spinach-associated food poisoning, I believe, that was a point when the regulator said, “oh, E coli bad,” which is unfortunate.

Dr Ruscio, DC:

But, thankfully there are other probiotics that are available in the states that are also beneficial. Okay. So after one month compared to lactulose, probiotics and Rifaximin led to improvements in serum ammonia, inflammatory cytokines, and probably most important, the outcome of improved cognitive function. Also probiotics led to the greatest improvements in the gut microbiota. So both probiotics and Rifaximin were effective, but there was a better outcome in the microbiota, which I would actually take with a grain of salt. I would look at the outcome first. Because if the patient feels better, that’s what we care about the most. And if the microbiota is saying the patient who is sick or doesn’t feel good has a healthier microbiota, then we’re probably not measuring things correctly. But since we see an equivalent symptomatic improvement in both groups (check, most important point) and we’re also seeing a healthier microbiota in the probiotic group, probably not surprising, then this is even further evidence showcasing how we should be really looking at probiotics as a fundamental therapeutic in so many conditions.

Dr Ruscio, DC:

And I want to just maybe pierce this a little bit further into your psyche. Sometimes you’re not feeling good. You have cognitive impairment, perhaps depression. You think “I want the big guns,” and stronger, harsher does not always mean better. And we should be thinking in this stepwise iterative process, diet and lifestyle first. Gut therapies have a few different levels to them. And at the end of the line in the gut therapy toolkit is when I think we should be reaching for an antibiotic like Rifaximin.

Dr Ruscio, DC:

Alrighty. The next study looked at the effect of Saccharomyces boulardii (this is the probiotic fungus) combined with triple therapy for H pylori. So this is the combination of antibiotics and antiacids and potentially bismuth. So in about 500 patients with H pylori, they were randomized to get bismuth, quadruple therapy, (so this is the two antibiotics, the antiacid, and the bismuth), triple therapy, or triple therapy plus a probiotic. And all patients were then retested with the urea breath test. One of the better tests for H pylori, not necessarily the best, but I would say PCR and breath tests are probably the two best as compared to the blood antibody test, which has some merit, but antibodies are like trying to diagnose a fire by finding smoke. And they’re not a guarantee. You want to see the actual fire, if you can.

Dr Ruscio, DC:

After six weeks, the eradication rates were better for the group that had either the probiotic (so triple therapy, plus Saccharomyces boulardii or the triple therapy plus the bismuth. So what we’re showing here is that for H Pylori triple therapy alone, two antibiotics, plus an an acid were not as effective as either adding probiotics or adding bismuth. So good news. And it absolutely maps onto the approach that we advocate for, which is if you’re going to use antimicrobial therapy, whether antibiotic or antimicrobial herbs, you want to leverage that with probiotics or bismuth.

Dr Ruscio, DC:

But the other thing here that I think we should probably weave into the dialogue, well, let me ask you this question. What, if anything, do you think would happen in the group that got the probiotic only? What other benefit do you think may have occurred in the group that was getting antibiotics? Because remember, they all get antibiotics, but only one group got antibiotics plus Saccharomyces boulardii. What one thing do you think may have happened in that group?

Dr Ruscio, DC:

Well, there was fewer patients that dropped out of the study because there was less distension, less belching, and less diarrhea. So there were similar eradication rates. There was better eradication with the addition of either the probiotic or the bismuth, but only the probiotic group saw the best resolution of symptoms. And this is probably twofold. One, the…Well actually, it’s mainly one fold. The microbiota was probably less disrupted from the co-administration of the probiotic. And I guess the twofold would be that the probiotics are also actively helping to reduce symptoms through their ability to quell leaky gut and some of the other mechanisms through which probiotics act. Having a net antihistamine effect would be another.

Dr Ruscio, DC:

So all of this information makes me just really have a hard time understanding why conventional medicine, in some circles, seems so slow to integrate probiotics into their care model. To be fair, there’s a decent number of conventional providers who are now recommending, “well you’re taking an antibiotic, take a probiotic along with it.” But there’s a surprising number who still are advising their patients not to, either from the SIBO community or in just really, I guess, sclerotic psychologically circles in conventional medicine. And what’s unfortunate is there’s just so much data that recommends and informs that we should be doing this, we should be coadministering probiotics along with antibiotics.


Hi, everyone. If case you are in need of help, or would like to learn more, I wanted to quickly point out what resources are available to you. “Healthy Gut, Healthy You”, my book and your complete self-help guide to healing your gut. If you’re not a do-it-yourselfer there is always the clinic and myself or any one of our doctors would be more than happy to help you. And as a quick aside there, we just had accepted for peer review a six-part case series where in we demonstrated the gut-thyroid connection and how crucially important it is to make sure you are not overlooking someone’s gut health as it pertains to thyroid health and thyroid symptoms more broadly. Through the clinic we also offer health coaching and, independent of the clinic, if you’re reading the book or need some general advice, we offer health coaching also. There’s our store where you can find our Elemental Diet line, our probiotic line, and other health and gut-supportive supplements. And finally, there is our clinician’s newsletter, the FFMR, AKA the Future of Functional Medicine Review database with research reviews, case studies, and other helpful resources for healthcare providers. Everything for any of these resources can be found at the overview page That’s

Dr Ruscio, DC:

The next study was a systematic review and meta-analysis of probiotics in the treatment of allergy (Allergic rhinitis). 30 randomized control trials in just over 2,700 patient with allergic rhinitis were randomized to placebo or probiotics. Very important because whenever we can parse out the placebo effect, that’s going to give us a truer representation of what effect you could expect to have. Probiotics led to improvements in quality of life and also in allergic rhinitis symptoms scores.

Dr Ruscio, DC:

So people felt better total quality of life, and they had less essentially runny nose. And what’s important here, I think, to keep in mind also is there was no change in blood eosinophils or IgE reactions between the groups. This is why it’s really important to look at lab values, but you won’t always see lab values improve even though the patient in front of you does. And this is one of the things that I feel to be so misguided about much of the field—sorry this is trite, but it’s always worth repeating—when people get wrapped up in, “we’ve got to test your histamine levels, we’ve gotta test your DAO levels, we got to do follow up testing,” because there’s not always, and in fact, many cases, especially with labs that are used in a more progressive and newer application, we don’t know how the biomarkers shift underneath a patient who’s seeing symptomatic improvements.

Dr Ruscio, DC:

And what’s unfortunate about that is if someone is feeling better, you want to follow that north star. You want to follow that lead and the biomarkers may lag behind. Or we may be looking at the wrong biomarkers. But, unfortunately, if someone’s feeling better and the biomarkers haven’t responded and then we start treating the biomarkers, we get the treating of the numbers paradigm. And there are certain places where that’s been validated, in areas that have a ton of study and evidence; cholesterol lowering, blood sugar lowering, blood pressure lowering, right? But when we get down to this sort of research, there’s a lot more that we don’t know than we do. Which is why you want to follow the metric that is the closest to the outcome you’re looking to get—I feel better. That’s what we want to treat for. In most cases, this is not an absolute rule. If the diabetic with a blood sugar of 200 says, “I feel better when I have a Slurpee.” Okay, well, we need to have a further conversation on this. But for many facets, especially in functional integrative medicine, we want to make the person’s subjectives, how they feel, the primary facet that we are pursuing.

Dr Ruscio, DC:

Okay. The next study: probiotics as an adjunctive therapy in chronic uticaria or hives. This was a randomized control trial, so we’re going to be controlling for placebo, 42 patients with chronic urticaria randomized to antihistamines alone or antihistamines plus probiotics. After two months, antihistamines plus probiotics led to greater improvements in urticaria scores, in quality of life scores. “But wait, were these histamine-free probiotics because urticaria hives, that’s a histamine mediated condition, and I’ve read that probiotics contain histamine and you had to have special histamine-free probiotics. Oh, by the way, where I read that was on the blog for the supplement company that sells this probiotic, but oh, never mind that.” No. Probiotics have a net antihistamine effect. Might there be one person in, I’m going to guess, a thousand for whom they need a low-histamine probiotic. Maybe. I’m always going to keep an open mind, but there is so much evidence showing that probiotics have a net antihistamine effect that it’s really silly to think that we need to be pursuing these special histamine-free probiotics. Because you’re missing the point, which is that the probiotics through their action have a strong net antihistamine effect.

Dr Ruscio, DC:

So we’re much better off personalizing the probiotic therapy to the individual rather than trying to find this probiotic that is much meticulously crafted based upon what mechanism we think we need to treat, right? Because if we get the probiotics right, we will reduce histamine, we will reduce leaky gut, we will combat H pylori, we will reduce other symptoms, we will combat SIBO. That’s really what we should be focusing on.

Dr Ruscio, DC:

Alrighty. The next study, looking at psoriasis treated via oral probiotics. This was a Streptococcus probiotic and this was a case-control 24-month longitudinal study. And they looked at 198 adults and children with psoriasis in a retrospective (looking back in time) application, looking at either topical ointment or the ointment plus probiotics. And remember this was the oral probiotics. So it wasn’t the topical probiotic. And at six months there was a greater benefit demonstrated in the probiotic group, complete remission of psoriasis in 55% of those receiving probiotics and 21% in the control group. And there was a lesser remission that they also quantified to 90% and 75% remission. And what you see is in each category, there is a strong favorability toward the addition of the probiotics. So there is your gut-skin connection.

Dr Ruscio, DC:

The next study looked at the effect of probiotic-assisted eradication on this more virulent form of H pylori. This is the CagA, C-A-G-A. […] So 168 patients with this, CagA virulence factor for H pylori—this is one of the more virulent strains of H pylori and there is evidence showing that this virulence factor does matter—they were randomized to receive, again, this bismuth quadruple therapy (so this is triple therapy, two antibiotics, and antiacid plus bismuth). So that’s the quad therapy. Or that therapy plus Saccharomyces boulardii. And what do you think happened after two weeks? The probiotic group experienced greater eradication rates, fewer adverse events, and quicker resolution of symptoms. So yeah, another study showing how important it is to use probiotics when we are administering antimicrobial therapy.

Dr Ruscio, DC:

In fact, I would go so far as to say that a sizeable number of patients will not need antibiotics if we get the probiotic protocol right. Not everyone. And I believe it was a 30% eradication shown with Saccharomyces boulardii when using probiotics alone. However, I would speculate that if that person had also improved their diet and their lifestyle, these things would improve the eradication rate. Would it be 80ish percent? Probably not, but we can always then add herbal antimicrobials or antibiotics. But if you’re trying to be judicious in your use of antibiotics, then certainly I think the herbals are a good stepping stone and then antibiotics, lastly. And also just remember that if you’re just targeting eradication, you’re partially missing the boat because we want eradication in the context of a patient that feels better.

Dr Ruscio, DC:

The next study looked at a gut microbiome-derived symbiotic formula as a novel adjunctive therapy for COVID 19. Now this is a symbiotic, just remember symbiotic is a probiotic plus a probiotic, so 55 COVID 19 hospitalized patients were randomized to either standard treatment or standard COVID treatment plus a symbiotic (AKA a probiotic with a probiotic). After one month of treatment, there was a greater antibody response in the symbiotic group, 88% versus 63%. And you want that robust antibody response. The probiotic group also had reduced inflammatory markers and lower nasal pharyngeal viral load. And I had mentioned this, gosh, now it’s maybe a year and a half ago. I made a, what I feel would be a reasonable, speculation that because we know at that time that probiotics reduced URTIs (upper respiratory tract infections), that it would probably hold true also for COVID. And this is the second or third study of its kind that’s been published in the past six months or so already.

Dr Ruscio, DC:

The next study looked at Bifidobacterium longum and infantis and its administration and its ability to reduce the incidence of Necrotizing enterocolitis in very low birthweight infants. And this Necrotizing enterocolitis is essentially an inflammatory issue that thwarts circulation and can lead to damage or death of intestinal tissue. And in the most severe cases, there can be a perforation of the intestinal wall and then sepsis. So this is definitely something that we want to prevent. They looked at 483 very low birthweight infants in the ICU and infants treated with probiotics experienced lower rates of Necrotizing enterocolitis (2.7% in the probiotic group and 11% in the control). And most importantly, reduced mortality—0% of those using the probiotic as compared to 2.7%. So probiotics led to a reduced risk of death in these pre-term infants from Necrotizing enterocolitis. This inflammation in the intestines that can lead to lack of blood supply and a perforation.

Dr Ruscio, DC:

And the next study looked at the effect of Bifidobacterium animalis and its impact on gastrointestinal symptoms. There was 14 studies looking at the impact and they found that Bifidobacterium animalis led to an increased defecation frequency, faster colon transit, improved stool consistency, but no change in abdominal pain or bloating. What I don’t love about this study is it’s only using one specific strain and with a specific species design…Actually, no, there’s no strain designation, but there is a species. So I just try to be careful because again, they’ll say strain, but they’re only mentioning this bacteria at the species level. So in any case, we would probably see a better effect if there was a multi-species probiotic that was used, but nevertheless, there’s the finding.

Dr Ruscio, DC:

Okay. So those are a number of updates on probiotics and hopefully you guys are enjoying this. A few, I guess, reminders and housekeeping items. If you have not yet left a review for the podcast, please, please, please. It is extremely helpful. And also remember that if you’re in need of help, the clinic is here to support you with the application of probiotics, diet, lifestyle measures, antimicrobials, immunoglobulins, elemental diets, histamine, MCAS, mold, thyroid, the whole array of things that we focus on. Which may seem divergent from one another but, boy, there is a whole heck of a lot of commonalities between how to successfully treat these conditions. In fact, really the diet, lifestyle, and gut health core of the model is such a powerful base from which we then can much more easily navigate the nuances of thyroid care, mold care, histamine, and MCAS.

Dr Ruscio, DC:

It’s also not to say that we have everything figured out, but that seems to be the best lever we can pull on. First, diet, lifestyle, gut health. And this can help, let’s say as one example, a patient who’s seen an MCAS specialist, and certainly this can help an individual but what I’ve seen in a number of cases now is the individuals don’t feel like it’s been a full causal treatment plan. They feel like they’re masking some symptoms, but something in their system still doesn’t feel right. They’re still battling with some symptoms. And I would argue quite strongly that we want to start with diet, lifestyle, and gut health because the amount of antihistamines and mast cell stabilizers that an individual will need is going to be less, as we discussed with some of this research even in this podcast alone, if you go through that first (the diet, lifestyle, and gut health therapies first), then you may not need any antihistamine or mast cell activation agents. Or only in a very sparing fashion.

Dr Ruscio, DC:

Joe and I are also getting a growing sense that some of the MCAS is really downstream, if not fully responding to diet, lifestyle, and gut health interventions, downstream to some sort of environmental trigger, often mold. And I think that’s important to keep in mind. That’s why over time, I’ve expanded the clinical model. And a big thank you to Joe for having his own personal experience with mold and bringing so much information on that to the table. It really helped accelerate my learning. And now we’re even better able to serve that small subset of patients who still exhibit all of this supplement, environment, and diet reactivity. And the more of these cases you see, there’s a signature of what a mold patient looks like. And, again, I think it’s important to point this out because this is how we’re trying to frame things and examine an individual at the clinic in terms of not do you fit the MCAS diagnostic criteria, because it doesn’t necessarily lead to treatments that I think are super effective, they do help, and I’m not going to refute that, and for a small number of patients they help a lot, but we’ve seen, or I can say I’ve seen enough patients now that have come from fairly well revered and published MCAS specialists, but still don’t feel like they are where they should be.

Dr Ruscio, DC:

And I think it’s because they just haven’t dove deeply enough into the upstream factors that are causing the downstream effect of the MCAS. And again, this is diet, lifestyle, and certainly going deep into the gut healing toolkit. And then in some cases looking into and resolving issues with mold. So just, I guess, a long reminder that if you’re in need of help, the clinic is more than happy to assist. And also, I should just mention one more time, I suppose, while we’re on the topic, that we’ve been noticing patients have or potential patients have questions, and we’ve set up a system now where you can do a free discovery call with our nurse Eliza. So she can answer questions for you that you may be wondering about, struggling with, and just get that bit of connection that’s hard to get from a website or just text or videos or what have you.

Dr Ruscio, DC:

Okay. So I guess that’s it guys, and I will look forward to catching up with you during the next podcast. All right. Thank you very much. Talk to you soon, byebye.


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➕ Dr. Ruscio’s, DC Notes

The Gut Microbiome in Depression and Potential Benefit of Prebiotics, Probiotics and Synbiotics: A Systematic Review of Clinical Trials and Observational Studies

  • 43 studies, 3,936 participants with depression
  • PRObiotics and synbiotics led to improvements in depressive symptoms, whereas PREbiotics had NO effect
  • Commentary: Another study showing the benefit of probiotics for depression. This highlights the gut-brain connection. 


Probiotic sepsis in preterm neonates-a systematic review

  • 1,569 studies on probiotics in preterm infants (<32 weeks old)
  • Sepsis caused by probiotics was confirmed in 25 cases
  • Commentary: This study showed a very small number of preterm infants developed sepsis from probiotics. Keep in mind that many other studies show significant benefit from probiotics for preterm infants in preventing necrotising enterocolitis, all-cause mortality and even sepsis. 


Do Probiotics in Pregnancy Reduce Allergies and Asthma in Infancy and Childhood? A Systematic Review

  • 6 studies 
  • Probiotics taken during pregnancy led to: 
    • NO change in atopic conditions in children in 2/6 studies
    • Less atopic conditions in children in 2/6 studies 
    • Less atopic conditions ONLY in children at high hereditary risk in 1/6 studies
  • Commentary: Inconsistent results were found for the effect of probiotics during pregnancy on incidence of atopic conditions in children.


Golden bifid might improve diarrhea-predominant irritable bowel syndrome via microbiota modulation

  • 21 IBS-D patients, all treated with probiotics 
    • 16/21 also diagnosed with SIBO 
  • After 1 month, probiotics led to improved IBS symptom scores, including: 
    • Abdominal pain (-1)
    • Abdominal distension (-0.7)
    • Diarrhea (-1.4)
    • Stool urgency (-1.1)
    • Incomplete evacuation (-1)
    • Depression (-2.9)
  • SIBO was eradicated in 25% 
  • Commentary: Probiotics led to improvements in IBS symptoms while also eradicating SIBO in a small proportion of patients.


Effect of a specific Escherichia coli Nissle 1917 strain on minimal/mild hepatic encephalopathy treatment

  • Open label study, 45 patients with hepatic encephalopathy (HE), randomized to: 
    • Lactulose
    • Rifaximin
    • Probiotic (E. coli Nissle 1917)
  • After 1 month, compared to lactulose, probiotic and rifaximin led to improved:
    • Serum ammonia
    • Inflammatory cytokines
    • Cognitive function
  • Probiotics led to the greatest improvement in gut microbiota
  • Commentary: Probiotics and rifaximin were both effective in improving HE. 


A multi-center, randomized controlled study on the effect of Saccharomyces boulardii combined with triple therapy for the initial eradication of Helicobacter pylori infection

  • 497 patients with H. pylori infection, randomized to:
    • Bismuth quadruple eradication therapy (BQT)
    • Triple eradication therapy (TT)
    • Triple therapy + S. boulardii (TT+S)
  • All patients received urea breath test after treatment
  • After 6 weeks, the eradication rates were:
    • 65% TT
    • 78% TT+S
    • 80% BQT
  • Compared to TT and BQT, TT+S led to: 
    • Fewer patients dropping out of the study
    • Less abdominal distension
    • Less belching
    • Less diarrhea 
  • Commentary: The addition of S. boulardii led to similar eradication rates as BQT and less GI symptoms. Fewer patients dropped out with the addition of S. Boulardii, possibly indicating greater tolerability of treatment.

Systematic review and meta-analysis of probiotics in the treatment of allergic rhinitis

  • 30 RCTs, 2,708 patients ith/ allergic rhinitis randomized to placebo or probiotics 
  • Probiotics led to improvements in: 
    • Quality of life score (-9.4)
    • Allergic rhinitis symptom score (-1.9)
  • NO change in blood eosinophils, allergic eye symptoms or antigen-specific IgE levels between groups
  • Commentary: Probiotics improved allergic rhinitis symptoms and quality of life. 


Probiotic as an adjuvant therapy in chronic urticaria: a blinded randomized controlled clinical trial

  • 42 patients with chronic urticaria, randomized to: 
    • Antihistamines alone (control)
    • Antihistamines + probiotics (intervention)
  • After 2 months, antihistamines + probiotics led to greater improvements in:
    • Urticaria scores (-21 intervention vs -18.4 control)
    • Quality of life (+66% vs +44%) 
  • Commentary: Addition of probiotics to antihistamine medication led to better clinical outcomes in patients with urticaria. 


Improvement of Psoriasis Using Oral Probiotic Streptococcus salivarius K-12: a Case-Control 24-Month Longitudinal Study

  • Retrospective study, 198 adults and children with psoriasis randomized to: 
    • Topical emollient
    • Topical emollient + probiotics
  • After 6 months, the probiotic group experienced greater rates of: 
    • Complete remission (55% probiotics vs 21% control)
    • 90% remission (75% vs 30.6%)
    • 75% remission (84% vs 42.8%) 
  • Commentary: Probiotics may be an effective therapy for treating psoriasis. This highlights the gut-skin connection. 


Effect of Probiotic-Assisted Eradication of cagA+/ vacA s1m1 Helicobacter pylori on Intestinal Flora

  • 168 patients with cagA+/vacA H. pylori, randomized to:
    • Bismuth quadruple therapy (BQT)
    • BQT + S. boulardii
  • After 2 weeks, the probiotic group experienced: 
    • Greater eradication rates (82% vs 77%)
    • Fewer adverse events (8% vs 25%
    • Quicker resolution of symptoms
  • Commentary: Another study showing the synergistic effect of adding probiotics to antimicrobial therapy in treating H. pylori, especially in reducing side effects. 


Gut microbiota-derived synbiotic formula (SIM01) as a novel adjuvant therapy for COVID-19: An open-label pilot study

  • 55 COVID-19 hospital patients randomized to:
    • Standard treatments (control) 
    • Standard treatment + synbiotics
  • After 1 month, treatment with synbiotics led to: 
    • Greater antibody response (88% synbiotic vs 63% control) 
    • Reduced inflammatory markers 
    • Lower nasopharyngeal viral load 
  • Commentary: Synbiotics can improve the immune response to a viral infection. 


Bifidobacteriumlongum subsp. infantis EVC001 Administration Is Associated with a Significant Reduction in the Incidence of Necrotizing Enterocolitis in Very Low Birth Weight Infants

  • Retrospective study, 483 very low birthweight infants in the ICU 
  • Infants treated with probiotics experienced:
    • Lower rates of necrotizing enterocolitis (NEC) (2.7% probiotics vs 11% control)
    • Reduced mortality from NEC (0% vs 2.7%)
  • Commentary: Probiotics led to reduced risk of death from NEC in very high risk infants.

Effects of Bifidobacterium animalis subspecies lactis supplementation on gastrointestinal symptoms: systematic review with meta-analysis

  • 14 studies on adults GI symptoms
  • Single-strain bifidobacterium animalis lactis probiotic led to:
    • Increased defecation frequency (small effect size) 
    • Faster colon transit time (small effect size) 
    • Improved stool consistency (moderate effect size) 
    • NO change in abdominal pain or bloating
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