Does your gut need a reset?

Yes, I'm Ready

Do you want to start feeling better?

Yes, Where Do I Start?

Do you want to start feeling better?

Yes, Where Do I Start?

Are Prescription Probiotics Worth It? Evaluating Pros and Cons

A Prescription Probiotic Isn’t Necessarily Better Than Over-The-Counter

When it comes to finding effective therapeutics, many people look for their doctors to recommend “professional-grade” products that can only be obtained with a prescription. Usually, this means medications, but sometimes it can also mean vitamins and supplements. 

In the case of probiotics, you’ll find far more over-the-counter (OTC) options than prescription options, but there are a couple of prescription probiotics you can only get through your doctor and some that have both a prescription or OTC option. 

Today we’ll take a look at these prescription probiotics and evaluate the pros and cons, comparing prescription to OTC probiotics, and looking at some of the research on different types of probiotics along the way. Let’s dive in. 

What are Probiotics for?

Probiotic supplements are typically single-species or multi-species combinations of beneficial bacteria that support gut health, a balanced immune system, hormone regulation, and many other aspects of human health. We now have decades of research supporting the efficacy and safety of probiotics [1, 2, 3, 4], and they are used to treat many conditions, from depression to inflammatory bowel disease.

The number of probiotic species in a supplement is measured by “colony-forming units” or CFUs. Most probiotics contain anywhere from a few CFUs up to 100 CFUs. A higher CFU count typically denotes a “stronger” probiotic, though different people will find probiotics effective at different CFU counts. 

For example, a person experiencing low-grade IBS symptoms like gas and bloating after meals may find relief from a 10 billion CFU probiotic, while someone with ulcerative colitis (an autoimmune inflammatory disease of the colon) may need a 60 billion CFU probiotic to see positive results. 

However, this is not always the case, and of course, other therapeutics may be necessary depending on the condition. Regardless, we have sound scientific evidence that probiotics are safe, beneficial, and effective at many dosages. Most probiotics will be taken daily, and they are commonly available as over-the-counter supplements. But, there are some probiotics that you can only get with a prescription from your doctor, which begs several questions.

  • Are prescription probiotics better than over-the-counter probiotics? 
  • What reasons would you choose a prescription probiotic? 
  • Are prescription probiotics common, or are they difficult to access? 

Let’s answer these questions. 

What are Prescription Probiotics and Should You Take Them?

There aren’t actually that many probiotics that you can only get with a doctor’s prescription — just two, in fact (as of the time of this writing). They are Visbiome Extra Strength 900 billion CFU and Restora RX.

Interestingly, while the Visbiome Extra Strength has a very high CFU count at 900 billion, Restora RX has only 12 billion CFUs, plus 1.25 grams of folic acid (vitamin B9). So it’s not just a high CFU count that makes a certain probiotic “prescription strength.” 

A few other probiotics, like Visbiome and VSL#3, are available as a prescription or over-the-counter, depending on your doctor’s recommendation and insurance coverage. 

Below is a breakdown of prescription probiotics products and popular over-the-counter (OTC) probiotics for comparison. All details were obtained directly from the manufacturer’s websites. The prescription-only probiotics are bolded within this table. 

BrandSpecies Included# of StrainsCFU CountCash Pay Price# of DosesAvailability
Visbiome Extra StrengthLactobacillus Bifidobacterium Streptococcus8900 billion$18730Prescription only
Visbiome (VSL#3 original formula)Lactobacillus Bifidobacterium Streptococcus8112.5 billion (capsule)
450 billion (powder)
$67 (capsules) 
$99 (powder)
60 (capsules) 
30 (powder)
Rx or OTC
VSL#3 (new formula)Lactobacillus Bifidobacterium Streptococcus8112.5 billion$5960Rx or OTC
Triple Therapy Probiotic Sticks by FMFLactobacillus Bifidobacterium Streptococcus Bacillus Saccharomyces boulardii + prebiotic1662 billion$10030OTC
1MD NutritionLactobacillus Bifidobacterium Bacillus1151 billion$4530OTC
TherBiotic Pro (IBS Relief) by KlaireLactobacillus Bifidobacterium321 billion$3521OTC
Culturelle Ultimate StrengthLactobacillus + prebiotic120 billion$2530OTC
Florajen DigestionLactobacillus Bifidobacterium515 billion$1930OTC
Restora RxLactobacillus + folic acid112 billion + 
1.25mg folic acid
$53 (varies per pharmacy)30Prescription only
FloraMend by ThorneLactobacillus Bifidobacterium35 billion$4930OTC

We can see from this chart that the two prescription-only probiotics lie at completely different ends of the CFU spectrum, and they have different species, strains, and costs. So are there any good reasons to get a prescription for either of these probiotics?

Restora RX contains only one probiotic strain at a lower CFU count of 12 billion. The manufacturer claims that the strain, a patented subtype of the Lactobacillus casei called KE-99, comes with claims of better absorption and efficacy [5]. 

They state that single-strain probiotics more easily attach to the GI wall, while multi-strain outcompete each other and are ultimately unable to colonize [6]. There are no human studies or clinical trials to substantiate these claims or show clinical benefit.

At this time, there’s no convincing evidence that getting highly specific by using strain subtypes is more beneficial than other probiotics.

Based on both research and my own clinical experience, it’s likely that this probiotic would not be as effective as a multi-species lacto-bifido blend probiotic [1, 2, 7]. At the most, it will be effective for certain people whose microbiome responds well to that specific strain, but you’re taking a pretty big chance on that. As for the financial side of things, Restora Rx is covered by select insurance companies, but you may need to pay cash for this prescription [5]. It’s about $53 out-of-pocket.

Bottom line? Restora RX may be worth trying with a doctor’s prescription if your insurance company covers it and you are under financial constraints. Otherwise, I would choose a reputable OTC multi-species blend instead.

The remaining prescription-only probiotic, Visbiome Extra Strength, comes in at 900 billion CFUs with 8 strains of Lactobacillus, Bifidobacteria, and Streptococcus species. For most people, I would say 900 billion CFUs is more than you need, but it may be worth trying if other multispecies probiotics have been ineffective or haven’t achieved the desired results. It’s likely that people with more debilitating digestive conditions, such as moderate-severe IBD, would be prescribed this extra-strength probiotic. 

However, this probiotic comes in at a higher out-of-pocket cost at $187, so some people may only find it worthwhile if their insurance company covers it. Again, only select insurance plans will cover this probiotic as a medical treatment.

Visbiome and VSL#3 Probiotics

We do have several studies showing the effectiveness of Visbiome and VSL#3 probiotics, which can be purchased with or without a prescription.

A meta-analysis of seven randomized controlled trials compared VSL#3 probiotic supplementation to fecal microbial transplant (FMT) in participants with active colitis [8].

Compared to the placebo, both VSL#3 and FMT were superior for inducing clinical response and remission. There was no significant difference between VSL#3 and FMT treatments. Neither treatment group had a significant risk of adverse effects.

Another meta-analysis assessed five studies with medicated, moderately active ulcerative colitis. They found that adding VSL#3 to their medication regimen induced remission in 44%, compared to placebo (25%). VSL #3 was determined to be safe and increase remission rates in ulcerative colitis non-responders [9].

A small 2021 RCT on 90 children with new-onset type 1 diabetes randomized participants to receive a placebo or Visbiome for 3 months [10]. Compared to the placebo, there was a significant decrease in HgA1c, required total insulin and bolus insulin (insulin administered with meals), and higher remission rates. 

This indicates a significant laboratory and clinical improvement in blood sugar dysregulation and underlying autoimmune processes due to Visbiome probiotic supplementation.

Overall, it appears that prescription probiotics are beneficial for human health, primarily for digestive diseases like IBS and IBD. However, these effects are no different from those seen using many OTC probiotics and are likely not unique to these formulas. They can be a great choice for those who have not responded to other conventional and/or holistic therapies, including standard probiotics.  

Higher CFU Count Isn’t Always Better

One of the appeals of prescription probiotics is a higher CFU count, as high as 900 billion for the VSL Extra Strength probiotics. 

If you haven’t seen results from lower CFU count probiotics in the past, this could be one reason to try prescription probiotics. But more doesn’t always mean better.

There is some evidence that potency matters, but it is much lower than the typical prescription probiotics, starting at just 10 billion CFU per day [1, 11, 12, 13]. What is more important is to have a high-quality, multi-strain probiotic that you can afford to stick with for a few months.

If you don’t see the benefit, you can start working your way up in potency, and if you have exhausted the use of lower-potency probiotics, high-potency, prescription probiotics can be a great next option.

You can learn more about my approach to starting a probiotic protocol in the probiotic starter guide

Cost of Prescription Probiotics vs. Over-the-Counter

In many ways, the choice to use prescription probiotics comes down to cost and whether or not your insurance company will cover it.

Without coverage, you can still get certain prescription probiotics if your doctor prescribes them for you, but you will have to pay out of pocket, or use qualifying HSA/FSA funds [14]. 

Ultimately, high-quality multi-species probiotics are available without a prescription, and are likely to be less expensive than non-covered prescription probiotics. For these reasons, I recommend most people start with OTC probiotics.

Debunking the Idea That Prescription = Better

At the end of the day, you are in charge of your health, and you decide if prescription probiotics are right for you. 

What I want to make abundantly clear is that prescription probiotics are not “better” simply because they require a doctor’s prescription to obtain them. There is a public perception that prescription probiotics are held to a higher standard than OTC probiotics. 

However, the Food and Drug Association (FDA) has not approved ANY probiotics for specific health conditions (15), meaning they cannot be categorized as a prescription medication and they are not subject to the rigorous standards of prescription pharmaceuticals. Even prescription probiotics suffer from the exact same quality control issues as OTC probiotics.

The best example of how this can go wrong is in the complex history between the two leading prescription probiotic brands: Visbiome and VSL#3. The short version is that the original VSL#3 formula was created by Professor Claudio De Simone in partnership with VSL Pharmaceuticals. Years later, Professor De Simone left the company, taking his creative property (the original VSL#3 formula). He later created Visbiome probiotics, using his original patented formula.

After the split, VSL Pharmaceuticals created an “identical” VSL#3 product with the same 8 strains and CFU potencies, but using a different manufacturer and manufacturing process. VSL Pharmaceuticals did not inform providers or patients that the formula had changed manufacturing processes and claimed that all prior conducted research was representative of the new VSL#3 product. Needless to say, it was not, and the new VSL#3 product had significant differences from the original formula, and Visbiome sued VSL#3 over intellectual property [16, 17, 18]. VSL Pharmaceuticals was determined to be guilty of false advertisement and trademark infringement.

The new VSL#3 was pulled from the shelves in 2018-2019, but is now available again as an OTC product and is still considered a top probiotic by physicians.

What’s the point of all of this? The Visbiome/VSL#3 drama shows that, for about 2-3 years, the #1 prescription probiotic amongst conventional and holistic providers suffered from significant quality control issues, and was falsely advertised. 

So I repeat, when it comes to nutritional supplements, prescription does NOT always mean higher quality. Seeking out an OTC brand that has been 3rd-party verified to contain what it claims to be is going to be the best option for most people. And if you are interested in a prescription probiotic, it’s still worthwhile to do your research on product quality first.

Working with a Gut Health Professional Can Make All the Difference in Your Recovery 

Probiotics can be a huge factor in recovery from gut health symptoms, prescription or otherwise. But no matter what therapies you try to fix your gut, you’ll be best served by a gut health professional who can guide you through the healing process and help you evaluate your diet, lifestyle habits, and other factors that affect your gut function. Having a partner in your healing can take some of the burden off of your shoulders and provide support when you need it. 

Reach out to us at the Ruscio Institute for Functional Health and schedule a free discovery call to see how we can help you along your healing journey.

The Ruscio Institute has developed a range of high-quality formulations to help our patients and audience. If you’re interested in learning more about these products, please click here. Note that there are many other options available, and we encourage you to research which products may be right for you.

➕ References

  1. Zhang X-F, Guan X-X, Tang Y-J, Sun J-F, Wang X-K, Wang W-D, et al. Clinical effects and gut microbiota changes of using probiotics, prebiotics or synbiotics in inflammatory bowel disease: a systematic review and meta-analysis. Eur J Nutr. 2021 Aug;60(5):2855–75. DOI: 10.1007/s00394-021-02503-5. PMID: 33555375.
  2. Zhang C, Jiang J, Tian F, Zhao J, Zhang H, Zhai Q, et al. Meta-analysis of randomized controlled trials of the effects of probiotics on functional constipation in adults. Clin Nutr. 2020 Oct;39(10):2960–9. DOI: 10.1016/j.clnu.2020.01.005. PMID: 32005532.
  3. American College of Gastroenterology Task Force on Irritable Bowel Syndrome, Brandt LJ, Chey WD, Foxx-Orenstein AE, Schiller LR, Schoenfeld PS, et al. An evidence-based position statement on the management of irritable bowel syndrome. Am J Gastroenterol. 2009 Jan;104 Suppl 1:S1-35. DOI: 10.1038/ajg.2008.122. PMID: 19521341.
  4. Ford AC, Quigley EMM, Lacy BE, Lembo AJ, Saito YA, Schiller LR, et al. Efficacy of prebiotics, probiotics, and synbiotics in irritable bowel syndrome and chronic idiopathic constipation: systematic review and meta-analysis. Am J Gastroenterol. 2014 Oct;109(10):1547–61; quiz 1546, 1562. DOI: 10.1038/ajg.2014.202. PMID: 25070051.
  5. Restora RXTM [Internet]. [cited 2023 Jul 27]. Available from:
  6. Probiohealth – Probiotics KE-99 – Probiotics supplements [Internet]. [cited 2023 Jul 28]. Available from:
  7. Goh KK, Liu Y-W, Kuo P-H, Chung Y-CE, Lu M-L, Chen C-H. Effect of probiotics on depressive symptoms: A meta-analysis of human studies. Psychiatry Res. 2019 Dec;282:112568. DOI: 10.1016/j.psychres.2019.112568. PMID: 31563280.
  8. Dang X, Xu M, Liu D, Zhou D, Yang W. Assessing the efficacy and safety of fecal microbiota transplantation and probiotic VSL#3 for active ulcerative colitis: A systematic review and meta-analysis. PLoS ONE. 2020 Mar 17;15(3):e0228846. DOI: 10.1371/journal.pone.0228846. PMID: 32182248. PMCID: PMC7077802.
  9. Mardini HE, Grigorian AY. Probiotic mix VSL#3 is effective adjunctive therapy for mild to moderately active ulcerative colitis: a meta-analysis. Inflamm Bowel Dis. 2014 Sep;20(9):1562–7. DOI: 10.1097/MIB.0000000000000084. PMID: 24918321.
  10. Kumar S, Kumar R, Rohilla L, Jacob N, Yadav J, Sachdeva N. A high potency multi-strain probiotic improves glycemic control in children with new-onset type 1 diabetes mellitus: A randomized, double-blind, and placebo-controlled pilot study. Pediatr Diabetes. 2021 Nov;22(7):1014–22. DOI: 10.1111/pedi.13244. PMID: 34174128.
  11. Li B, Liang L, Deng H, Guo J, Shu H, Zhang L. Efficacy and Safety of Probiotics in Irritable Bowel Syndrome: A Systematic Review and Meta-Analysis. Front Pharmacol. 2020 Apr 3;11:332. DOI: 10.3389/fphar.2020.00332. PMID: 32317962. PMCID: PMC7147251.
  12. Wang L, Guo M-J, Gao Q, Yang J-F, Yang L, Pang X-L, et al. The effects of probiotics on total cholesterol: A meta-analysis of randomized controlled trials. Medicine (Baltimore). 2018 Feb;97(5):e9679. DOI: 10.1097/MD.0000000000009679. PMID: 29384846. PMCID: PMC5805418.
  13. Ouwehand AC. A review of dose-responses of probiotics in human studies. Benef Microbes. 2017 Apr 26;8(2):143–51. DOI: 10.3920/BM2016.0140. PMID: 28008787.
  14. What Vitamins Are FSA/HSA Eligible? [Internet]. [cited 2023 Jul 27]. Available from:
  15. Statement from FDA Commissioner Scott Gottlieb, M.D., on advancing the science and regulation of live microbiome-based products used to prevent, treat, or cure diseases in humans | FDA [Internet]. [cited 2023 Jul 25]. Available from:
  16. Douillard FP, Mora D, Eijlander RT, Wels M, de Vos WM, PLOS ONE Editors. Correction: Comparative genomic analysis of the multispecies probiotic-marketed product VSL#3. PLoS ONE. 2018 Aug 30;13(8):e0203548. DOI: 10.1371/journal.pone.0203548. PMID: 30161239. PMCID: PMC6117072.
  17. Palumbo P, Lombardi F, Cifone MG, Cinque B. The Epithelial Barrier Model Shows That the Properties of VSL#3 Depend from Where it is Manufactured. Endocr Metab Immune Disord Drug Targets. 2019;19(2):199–206. DOI: 10.2174/1871530318666181022164505. PMID: 30360752. PMCID: PMC6425067.
  18. Trinchieri V, Laghi L, Vitali B, Parolin C, Giusti I, Capobianco D, et al. Efficacy and Safety of a Multistrain Probiotic Formulation Depends from Manufacturing. Front Immunol. 2017 Nov 6;8:1474. DOI: 10.3389/fimmu.2017.01474. PMID: 29163538. PMCID: PMC5681494.

Getting Started

Book your first visit


I care about answering your questions and sharing my knowledge with you. Leave a comment or connect with me on social media asking any health question you may have and I just might incorporate it into our next listener questions podcast episode just for you!