In addition to peppermint oil, other herbal products have been studied for IBS, but there has only been a small amount of research on them, and much of it is of limited quality.

• A 2018 analysis of 3 studies in 326 people suggested that curcumin, a substance found in the herb turmeric, may have a potential benefit for treating symptoms in some people with IBS. The quality of the evidence was very low, however, and there wasn’t enough evidence to know for sure if it is helpful. Although in the past turmeric had been considered safe, recent research has raised concerns about a potential association between turmeric and liver injury in a small number of people with certain genes.

NatureWise, Turmeric Curcumin, 90 Vegan Capsules
Also at iHerb

Probiotics are live microorganisms (such as bacteria and yeast) that can be taken as dietary supplements or included in yogurt and other fermented foods and some beauty products. 

Some evidence suggests that some probiotics may improve IBS symptoms; but the evidence is not conclusive. Some probiotics seem to be more effective than others, depending on whether they’re used alone or in different combinations.

• According to practice guidelines from the American College of Gastroenterology (2021), there’s not enough strong evidence on the effectiveness of probiotics for IBS to recommend their use. The guidelines say that the current evidence for this recommendation is very weak, however, because many different types of probiotics have been studied, and most of the studies have been small, with mixed results.
• A 2022 review and analysis of 10 studies in 757 people with constipation-predominant IBS found that probiotics improved stool consistency but did not help reduce pain or bloating or improve quality of life. The quality of the evidence in the reviewed studies was low.
• A 2021 review and analysis of 9 studies in 651 children with IBS found that children who took probiotics had less severe and less frequent abdominal pain than those who took a placebo (fake treatment). Different studies used different doses and types of probiotics, however, and it is not clear how the size of the probiotic dose relates to pain in children with IBS.
• A 2020 review and analysis of 35 studies involving 3,452 people with IBS found that taking probiotics for 4 weeks may help relieve IBS symptoms such as abdominal pain, bloating, and gas. Better results were obtained with combination probiotics than single probiotics. However, because of small study sizes and differences in the types of probiotics and methods used in the studies, it is not clear which types of probiotics are the most effective.
• A 2019 review and analysis of 14 studies in 1,695 people with IBS reported that daily doses of probiotics containing Lactobacillus and Bifidobacterium microorganisms relieved overall IBS symptoms more than daily doses of a single probiotic.
• Probiotics have an extensive history of apparently safe use, particularly in healthy people. However, few studies have looked at the safety of probiotics in detail, so there’s a lack of solid information on the frequency and severity of side effects. The risk of harmful effects from probiotics is greater in people who are seriously ill or have compromised immune systems.
• In people with IBS, probiotics usually have only minor side effects, if any. Side effects that have been reported include cramping and nausea. Rarely, more serious side effects have been reported, including infections and acidosis, a potentially life-threatening condition where there is too much acid in the body.
• Most research about the safety of probiotics comes from studies of Lactobacillus and Bifidobacterium; less is known about other probiotics.

Top 5 Probiotics for Kids: Boosting Digestive Health & Immunity

Probiotics have the ability to balance the gut flora in children, promote digestive system health, enhance immunity, and also help alleviate specific conditions.

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• Prebiotics are nondigestible ingredients in food or dietary supplements that support the growth or activity of beneficial gut bacteria.
• A 2019 review and analysis of 11 studies in 729 people with IBS or other functional bowel disorders found that taking prebiotic supplements did not improve GI symptoms or quality of life. Moderate amounts of some prebiotics, specifically less than 6 grams/day of non-inulin-type fructans, improved gassiness. However, other prebiotics (inulin-type fructans) had the opposite effect; they increased gassiness in people with IBS.
• Prebiotics have a long history of safe use. However, when taken in large doses (more than 20 grams per day for an adult), they can have side effects including gassiness, bloating, abdominal pain, cramps, and diarrhea.

Dr. Tobias, Prebiotics, 30 Capsules
Also at iHerb

• A small amount of evidence suggests that yoga and other types of exercise may be helpful for IBS. A 2022 review of 5 studies in 218 people with IBS reported improvement in IBS symptoms but not pain or quality of life from doing yoga. The authors of the study cautioned, however, that the quality of the evidence was very low.
• Yoga is generally considered a safe form of physical activity for healthy people when performed properly, under the guidance of a qualified instructor. However, as with other forms of physical activity, injuries can occur. The most common injuries are sprains and strains. Serious injuries are rare. The risk of injury associated with yoga is lower than that for higher impact sports activities.

There is little research on the benefits of meditation and mindfulness for improving health in people with IBS, and the results are not conclusive.

• A 2018 review of 5 studies in 695 people concluded that in addition to receiving conventional care, participating in online mindfulness along with education or cognitive behavioral therapy can benefit general health in people with health conditions including IBS.
• A 2019 review and analysis of 2 studies in 165 people reported that mindfulness meditation training did not improve IBS symptoms, based on low-quality evidence.
• Meditation and mindfulness practices usually are considered to have few risks. However, few studies have examined these practices for potentially harmful effects, so it isn’t possible to make definite statements about safety.

There has been a small amount of research on the use of relaxation therapy for IBS.

• A 2021 review and analysis of 6 studies in 278 people with IBS reported that relaxation therapy was not helpful for abdominal pain or overall symptoms from IBS.
• Relaxation techniques are generally considered safe for healthy people. In most research studies, there have been no reported negative side effects. However, occasionally, people report negative experiences such as increased anxiety, intrusive thoughts, or fear of losing control. 
• There have been rare reports that certain relaxation techniques might cause or worsen symptoms in people with epilepsy or certain psychiatric conditions, or with a history of abuse or trauma.

The research on acupuncture for IBS is mixed. When compared with sham (fake) acupuncture, real acupuncture does not improve IBS symptoms. However, research that compared acupuncture to various medications found that acupuncture was more effective in relieving IBS symptoms.

• A 2021 review and analysis of 24 studies in 3,220 people with IBS found that in studies comparing acupuncture to various medications, acupuncture was more effective in relieving IBS symptoms. When used in combination with other treatments including medicines or herbs, acupuncture helped to improve their effectiveness in treating IBS symptoms. However, acupuncture did not work better than sham acupuncture for improving IBS symptoms. The authors noted that the quality of the evidence was low to moderate in the reviewed studies.
• Relatively few complications from using acupuncture have been reported. However, complications have resulted from use of nonsterile needles and improper delivery of treatments.
• When not delivered properly, acupuncture can cause serious adverse effects, including infections, punctured organs, and injury to the central nervous system.
• The U.S. Food and Drug Administration (FDA) regulates acupuncture needles as medical devices and requires that they be sterile and labeled for single use only.

A 2020 analysis of 53 studies looked at using a variety of complementary psychological and physical approaches in adults and children with IBS. Among the included approaches were various relaxation techniques, yoga, meditation, hypnosis, and biofeedback (i.e., using breathing or information from external devices to learn how to control heart rate or other body functions). The authors concluded that, when used together with medicinal treatment, these complementary psychological and physical approaches along with conventional psychological therapies, such as psychoeducation and cognitive behavioral therapy, can help reduce IBS symptom severity. They also found that different complementary psychological and physical approaches appear to be equally effective; none appears to be more effective than the others.