The Ultimate Guide To The Best Probiotics For IBS

Irritable bowel syndrome (IBS) is a gastrointestinal disorder that can lead to several uncomfortable symptoms such as diarrhea, cramping, gas, bloating, and abdominal pain. Its precise cause remains unknown.

However, recent studies suggest that IBS can be caused by an imbalance in the microorganisms living in the digestive tract and a malfunctioning intestinal barrier¹ whose role is to allow nutrients to absorb into the bloodstream while keeping potentially harmful contents in the intestine.

Your digestive tract is home to a large number of bacteria and microscopic organisms known as gut flora. In fact, there are ten times as many microorganisms as there are cells in your digestive tract². Generally, a good balance in the intestinal microbiome is essential to help your body function optimally and stay healthy.

Many clinical trials have been conducted to determine whether probiotics can help treat IBS. The theory behind these studies is that adding probiotics to the digestive system can help reduce harmful bacteria and, in turn, control IBS symptoms.

Keep reading for a comprehensive guide to the best probiotics for IBS.

Have you considered clinical trials for Irritable bowel syndrome (IBS)?

We make it easy for you to participate in a clinical trial for Irritable bowel syndrome (IBS), and get access to the latest treatments not yet widely available - and be a part of finding a cure.

What are probiotics?

Probiotics are live microorganisms considered beneficial bacteria. These microorganisms are essential to the human body for both the oral and gut microbiome. When we talk about taking probiotics for IBS, we mean consuming dietary supplements or foods that contain probiotics.

The gut microbiota consists of thousands of different species of good bacteria, and probiotics can alter them for the better by helping the level to remain balanced. Some of the harmful bacteria include Clostridium perfringens, E. coli, and Staphylococcus.

In dietary supplements, probiotics help with several issues such as autoimmune diseases, digestive health, and IBS. In addition, they can also help neurocognitive conditions³, including obsessive-compulsive disorder, Parkinson's disease, and depression.

Probiotics consist of a single or mixed culture of strains and species in specific doses that can work to benefit the health in a number of ways.

The most common probiotic strains present in dietary supplements and foods are:

  • Lactobacillus rhamnosus

  • Lactobacillus casei

  • Bifidobacterium bifidum

  • Lactobacillus acidophilus

  • Lactobacillus plantarum

  • Bifidobacterium lactis

  • Bifidobacterium animalis

  • Bifidobacterium infantis

  • Some specific Streptococcus strains

Can probiotics help treat IBS?

The balance in gut microbiota in people with IBS is different from that in people without this condition. In many clinical trials, probiotics were found to support the health of people with IBS.

To put it simply, when you take a probiotic supplement, the number of friendly bacteria increases in the large intestine.

Therefore, probiotics help:

  • Strengthen the intestinal lining and reduce intestinal permeability

  • Decrease visceral hypersensitivity

  • Eradicate small intestinal bacterial overgrowth (SIBO)

  • Reduce pain by affecting nerve receptors found in the lining of the intestines

  • Normalize intestinal motility

  • Reduce "unfriendly" bacteria

Specific probiotics target specific symptoms, and ten probiotic strains are found to improve overall IBS symptoms⁴. These symptoms include:


About 15%⁵ of patients with IBS have diarrhea. To counteract this symptom, the best probiotic to take is Bacillus coagulans, which has been shown to improve multiple symptoms, including stool frequency and diarrhea, and Saccharomyces boulardii (probiotic yeast) helps treat diarrhea-predominant IBS (IBS-D).


The constipation-predominant type (IBS-C) is the most common form of IBS and affects about 50%⁵ of all people with the disorder.

Studies to establish the benefits of two multi-strain probiotics (L. acidophilus and L. reuteri, and L. plantarum, L. rhamnosus, and L. lactis) show improvements to the frequency of normal bowel movements and a reduction of negative symptoms. The probiotics increased bowel movements and improved their consistency.

Abdominal pain

Abdominal pain is a common symptom among patients with IBS. This can be felt solely in the lower abdomen or across the entire abdomen, which can subside after a bowel movement.

Seven probiotics⁴ have shown improvements in these symptoms, namely:

  • S. cerevisiae

  • L. plantarum

  • B. lactis

  • B. bifidum

  • L. casei

  • L. acidophilus

Bloating and gas

Patients with IBS also experience increased sensitivity that can lead to uncomfortable bloating and gas. The strains that help improve these symptoms include L. plantarum, B. lactis, L. bulgaricus, L. acidophilus, and S. thermophilus.

Which probiotics should I take for IBS?

Clinical trials⁶ have revealed the best probiotics for improving the symptoms of IBS contain strains such as:

  • Saccharomyces boulardii

  • Bifidobacterium lactis

  • Lactobacillus acidophilus

  • Bifidobacterium lactis

  • Bifidobacterium infantis

  • Bifidobacterium lactis

  • Lactobacillus plantarum

Can probiotics ever make IBS worse?

Probiotic products can worsen or even induce symptoms in some people, whether they have IBS or not. People may report temporary gas and bloating in their first weeks of taking probiotics. Besides this, probiotics may cause side effects and symptoms in people who have certain food allergies or medical conditions, depending on the ingredients.

Although there is no assurance that a probiotic will work, most individuals won't experience any serious side effects. But if you have concerns about the safety of a product, you should check with the manufacturer. Also, read the instructions before using any product and ensure you do not exceed the recommended dosage. Individuals with allergies must check the label for potential allergens.

Unlike the strict regulations set by the US Food and Drug Administration (FDA) for many food and medical products, the rules that apply to probiotic supplements are inconsistent in the US.

Accordingly, the regulations for probiotics depend on the manufacturer deeming the product a dietary supplement, food, drug/biologic, or cosmetic product. However, under NDI guidance⁷, probiotic bacteria are considered dietary ingredients when consumed as food, which means it gets FDA protection. This can give you peace of mind that you can take them safely.

Should you see a doctor before you start taking probiotics for IBS?

Probiotics may not cause side effects for most healthy individuals, but this doesn't mean they're good for everyone. Like any other over-the-counter product, you should see a doctor before you start taking probiotic supplements. If you have a weakened immune system, certain medical conditions, or food allergies, your healthcare provider may advise you against taking them.

The lowdown

Probiotics are essential strains of yeast or live bacteria, and taking them regularly can help create a balanced gut microbiota. Therefore, it may help treat several health conditions, including IBS,  which is caused by an overgrowth of harmful bacteria.

Probiotics are safe, with side effects, if experienced at all, that are usually short-lived and mild. But if any reaction raises concern, you may need to reduce the dosage, try a different strain or stop using it altogether. Talk to your doctor about any persistent or severe side effects.

Have you considered clinical trials for Irritable bowel syndrome (IBS)?

We make it easy for you to participate in a clinical trial for Irritable bowel syndrome (IBS), and get access to the latest treatments not yet widely available - and be a part of finding a cure.

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