Bacillus Coagulans

This good bacteria may help ease IBS symptoms

Bacillus Coagulans tablets and powder

Verywell / Anastasia Tretiak

Bacillus coagulans (B. coagulans) is a probiotic. Probiotics are typically "good" microorganisms (small living things).

In general, probiotics work by helping your body have a healthy community of microorganisms. This is essential for things like your immune health and more.

Probiotics may also make certain substances that have beneficial effects on your body.

In particular, B. coagulans may relieve constipation and irritable bowel syndrome (IBS) symptoms.

This article discusses what you should know about B. coagulans—the bacteria's potential uses, side effects, and interactions.

Dietary supplements are not regulated like drugs in the United States, meaning the Food and Drug Administration (FDA) does not approve them for safety and effectiveness before products are marketed. When possible, choose a supplement tested by a trusted third party, such as USP, ConsumerLab, or NSF. However, even if supplements are third-party tested, that doesn't mean they are necessarily safe for all or effective in general. Therefore, talking to a healthcare provider about any supplements you plan to take and checking in about potential interactions with other supplements or medications is essential.

Supplement Facts

  • Active ingredients(s): Bacillus coagulans
  • Alternative name(s): Bacillus coagulans, B. coagulans, probiotic, Bacillus bacteria, Bacillus probiotics
  • Legal status: Over-the-counter supplement. (United States)
  • Suggested dose: May vary based on the specific B. coagulans strain, dosage form, medical condition, and your age
  • Safety considerations: Pregnancy and breastfeeding. People with compromised immune systems. Side effects and medication interactions are possible.

Uses of Bacillus Coagulans

Supplement use should be individualized and vetted by a healthcare professional, such as a registered dietitian, pharmacist, or healthcare provider. No supplement is intended to treat, cure, or prevent disease.

Like many natural products, people may take B. coagulans for various reasons—mainly relating to the digestive system.

Irritable Bowel Syndrome

According to a review, eight weeks of B. coagulans may effectively relieve irritable bowel syndrome (IBS) symptoms, which may include pain, bloating (gas), and straining.

In IBS, some people might experience more diarrhea. This is called diarrhea-predominant IBS.

In a small clinical trial, people with this type of IBS benefited from taking a specific MTCC 5856 strain of B. coagulans in addition to the standard of care.

The B. coagulans dosage was two billion colony-forming units (CFUs) daily for 90 days.

Participants taking B. coagulans experienced fewer of the following symptoms:

  • Diarrhea
  • Gas
  • Stomach pain
  • Vomiting

In addition to less severe IBS, these participants reported better quality of life.

While these results look promising, larger, higher-quality studies are still necessary.


In a small clinical trial, study participants were divided based on their main symptoms or digestive problem.

Participants were either in constipation or diarrhea groups.

And all participants took one billion colony-forming units (CFU) of B. coagulans by mouth twice daily for four weeks.

Based on a study, people with constipation or diarrhea problems may benefit from B. coagulans.

B. coagulans may be more effective at relieving constipation symptoms.

But longer-term clinical trials with a larger group of people are necessary to assess this effect better.

What Are the Side Effects of Bacillus Coagulans?

 Like many medications and natural products, side effects are possible with B. coagulans.

Common Side Effects

A limited number of clinical trials studied probiotic side effects in detail.

However, one study reported no side effects with a specific LBSC strain of B. coagulans.

Moreover, the Food and Drug Administration (FDA) placed B. coagulans on its GRAS list. GRAS stands for substances that are generally recognized as safe.

Severe Side Effects

The same study showed no serious side effects with B. coagulans. However, a severe allergic reaction is a serious side effect possible with any medication.

If you're having a severe allergic reaction to B. coagulans, symptoms may include breathing difficulties, itchiness, and rash.

Other potentially serious side effects of probiotics may also include:

  • Infection risk
  • Severe side effects from harmful substances made by bacteria in the probiotic product
  • Antibiotic resistance
  • Health risks from contaminants

While typically rare, serious side effects are possibly more likely in people with severe medical conditions or a weakened immune system (the body's defense system).

Call 911 and get medical help immediately if you have a severe allergic reaction or if any of your symptoms are life-threatening.

Bacillus Coagulans capsules
Verywell / Anastasia Tretiak


A healthcare provider may advise against taking B. coagulans if any of the following applies to you:

Severe allergic reaction: You shouldn't take this medication if you have a severe allergic reaction to B. coagulans or any of its components (ingredients or parts).

Pregnancy or breastfeeding: There are a few product labels that target either pregnant or breastfeeding people. But there isn't enough information about the effects and safety of B. coagulans while pregnant or breastfeeding. For this reason, contact a healthcare provider to discuss the benefits and risks before taking B. coagulans.

Children: There are a few product labels that target children. Dosages of up to 100 million colony-forming units (CFU) of B. coagulans per day for up to one year are likely safe in even infants.

But premature infants might have a higher risk of severe side effects. If you consider B. coagulans for your child, talk with their healthcare provider.

Older adults over 65 years: Older adults participated in some B. coagulans-related clinical trials, but these studies were small. Many available studies included a larger group of younger adults. Moreover, some older adults may be more likely to have medication side effects. For this reason, take B. coagulans with caution.

People with severe medical conditions: People with severe medical conditions have a higher risk of serious side effects from probiotics. For example, someone in the hospital for a severe medical condition should likely avoid probiotics.

People with a weakened immune system: People with a weakened immune system are more likely to experience severe side effects from probiotics. For example, people with human immunodeficiency virus (HIV) might have a higher risk of infections from probiotics.

Dosage: How Much Bacillus Coagulans Should I Take?

Always speak with a healthcare provider before taking a supplement to ensure that the supplement and dosage are appropriate for your individual needs.

While there are some studies on B. coagulans in humans, additional larger, longer-term, and well-designed clinical trials are still necessary.

For this reason, there are no guidelines on the appropriate dosage to take B. coagulans for any condition.

But for adults with irritable bowel syndrome (IBS), the dosage is likely one billion colony-forming units (CFU) twice daily or two billion CFU once daily for four to 12 weeks.

If you take B. coagulans, follow a healthcare provider's recommendations or label instructions.

What Happens If I Take Too Much Bacillus Coagulans?

There is little information about B. coagulans' toxicity and overdoses in humans.

However, 100 million colony-forming units (CFU) daily for up to a year is typically safe in infants.

It's usually safe for adults to take up to six billion CFU daily for up to three months.

And at lower doses, adults may safely take B. coagulans for up to one year.

Above these doses, symptoms of overdoses with B. coagulans are likely similar to its potentially severe side effects.

And since some probiotic products might contain contaminants with "unlisted" microorganisms, health risks from these microorganisms are also possible

If you suspect you're experiencing life-threatening side effects, seek immediate medical attention.


Since B. coagulans is a type of bacteria, B. coagulans and antibiotics might change each other's effectiveness. But there is limited data about this potential interaction.

For this reason, a pharmacist or healthcare provider may recommend separating probiotics and antibiotics by at least two hours.

They may also suggest waiting until you finish your course of antibiotics and then starting probiotics after.

It is essential to carefully read a supplement's ingredients list and nutrition facts panel to learn which ingredients are present and how much of each ingredient is included. Please review this supplement label with a healthcare provider to discuss potential interactions with foods, other supplements, and medications. 

How to Store Bacillus Coagulans

Since storage instructions may vary for different natural products, carefully read the directions and packaging label on the container.

Keep your medications tightly closed and out of the reach and sight of children and pets, ideally locked in a cabinet or closet.

The optimal storage condition for medicines is in a cool and dry place. Some probiotics may also need to be stored in the refrigerator.

Discard after one year or as indicated on the packaging. Avoid putting unused and expired medicines down the drain or in the toilet. Visit the FDA's website to know where and how to discard all unused and expired medicines. You can also find disposal boxes in your area.

Please ask a pharmacist or healthcare provider any questions about how to take care of your medications or supplements.

Similar Supplements

B. coagulans might effectively relieve irritable bowel syndrome (IBS) symptoms. So, another potentially similar supplement is peppermint oil.

Peppermint oil might temporarily relieve IBS symptoms, such as bloating (gas) and stomach pain.

Please don't combine multiple supplements until you first talk with a registered dietitian nutritionist, healthcare provider, or pharmacist.

Checking in can help you avoid possible interactions and side effects and ensure you're giving these supplements a fair trial at appropriate doses.

Frequently Asked Questions

  • What is the most common dosage form of Bacillus coagulans?

    B. coagulans is available in several different dosage forms—with capsules potentially being the most common.

  • Is Bacillus coagulans products from manufacturers in the United States?

    Yes. There are B. coagulans products made by manufacturers in the United States.

  • What is the difference between probiotic, prebiotic, and postbiotic?

    Probiotics are "good" bacteria that help your body keep a healthy community of microorganisms (small living things).

    Prebiotics encourage the growth and activity of "good" bacteria in your body.

    Postbiotics are substances made by "good" bacteria that benefit your body.

  • Is a single or combination probiotic better?

    A combination probiotic might have more additive health benefits, but more research is necessary.

  • How do I take Bacillus coagulans safely?

    In general, to safely take natural products—like B. coagulans—inform your healthcare provider, registered dietitian nutritionist, and/or pharmacist about any medication change. This includes over-the-counter (OTC), herbal, natural medications, and supplements.
    They can help prevent possible interactions and side effects. They can also ensure you’re giving B. coagulans a fair trial at appropriate doses.

Sources of Bacillus Coagulans & What to Look For

There are several different sources of B. coagulans.

Food Sources of Bacillus Coagulans

B. coagulans is a type of bacteria. In the United States, the FDA approved a specific B. coagulans as a substance added to food.

Presently, Lactobacillus and Bifidobacterium bacteria are commonly used in probiotic foods.

But since they're not heat-resistant, there is also a growing interest in using B. coagulans in the food industry.

Bacillus Coagulans Supplements

B. coagulans is available in several forms, including capsules and tablets.

If you have difficulties swallowing pills, B. coagulans might also be available in the following dosage forms:

  • Gummies
  • Liquid
  • Lozenges
  • Powder
  • Wafers

Vegetarian and vegan options might also be available.

You may also see B. coagulans as a stand-alone supplement or combined with other probiotics or active ingredients.

Your specific product will depend on your preference and health goals.

Each product may work a bit differently, depending on the form.

So, following a healthcare provider's recommendations or label directions is important.


B. coagulans is a type of bacteria. It's a probiotic, a "good" bacteria that help your body keep a healthy community of microorganisms (small living things).

B. coagulans might effectively relieve constipation and irritable bowel syndrome (IBS) symptoms. But similar to many medications and supplements, side effects and interactions are still possible.

Additional higher-quality, longer-term, and larger clinical trials are still necessary to better evaluate the effectiveness and safety of B. coagulans.

Before taking B. coagulans, involve a registered dietitian nutritionist, pharmacist, or healthcare provider to help you safely achieve your health goals.

15 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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Additional Reading

By Ross Phan, PharmD, BCACP, BCGP, BCPS
Ross is a writer for Verywell with years of experience practicing pharmacy in various settings. She is also a board-certified clinical pharmacist and the founder of Off Script Consults.