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Irritable bowel syndrome: What helps – and what doesn’t

Created: ; Last Update: October 20, 2016; Next update: 2019.

There are a lot of treatments for the relief of irritable bowel syndrome (IBS) – but there is a lack of good-quality research on them. Because the causes of IBS are not clear, it is difficult to find suitable treatments. But research has suggested that at least some medications and treatments may help.

The main symptoms of irritable bowel syndrome are abdominal pain, constipation and diarrhea. Most people only have mild symptoms that they can cope with fairly well without having treatment. Over time they learn to understand their body's signals. But some people have such severe symptoms that their everyday lives are greatly affected and it becomes very distressing. If that is the case, various treatment options can be considered.

Research on IBS treatments

Unfortunately, many of the studies on IBS treatments are not very conclusive. Because these studies often only lasted a few weeks, it is not clear how long the treatment effects last, or whether the treatments still provide relief when used for a longer time. Also, there is not enough research on most of these treatments to be able to tell whether the type or severity of symptoms influences the success of the treatment: For instance, some treatments might be more effective in people who mostly have diarrhea rather than constipation. This has not been properly accounted for in many studies. But research has indicated what treatments might be worth trying out – and has suggested which of them are the best tolerated and safest.

What role does diet play?

Most people who have IBS find that certain foods improve their symptoms, or make them worse. Unfortunately, there is very little good research on how diet may affect the symptoms – but that's not to say that it plays no role. Reactions to specific foods vary a lot from person to person, and it often takes a while to figure out what helps and what doesn't.

It might help to keep a food diary for a few weeks. You can write down what you eat over the course of the day, whether you have any symptoms and, if so, what kind. You can also mention any other factors that might explain the symptoms (such as stress at work). You may gradually start recognizing patterns that help you identify which foods you don't tolerate. You can show your doctor the diary to talk about whether it would be a good idea to stop eating certain foods.

Does avoiding fermentable carbohydrates (low FODMAP diet) help?

In recent years, IBS has increasingly been associated with foods containing fermentable carbohydrates. These are known as FODMAPs, which stands for "fermentable, oligo-, di-, mono-saccharides and polyols." They are found in many foods, including fructose (a monosaccharide), lactose and starch (oligosaccharides) and sweeteners (sugar alcohols). It is believed that the absorption of FODMAPs in the body can result in more liquid in the intestine, which increases the risk of diarrhea. As these carbohydrates ferment, more gas is produced in the intestine too, causing bloating and wind. The composition of the intestinal bacteria is also influenced by diet.

In the low FODMAP diet, you do not eat any foods containing these sugars. But this increases your risk of malnutrition because it is then difficult to get enough vitamins and minerals in your diet. It is also hard to keep up such a strict diet in day-to-day life.

There has not yet been any good-quality research proving that the low FODMAP diet can relieve IBS symptoms. Medical experts do not generally recommend this diet.

Can extra fiber help?

People who have IBS are often advised to eat more fiber. There are two different types of dietary fiber:

  • Soluble fiber, which absorbs water in the bowel (e.g. psyllium, also called isphagula)
  • Insoluble fiber, which hardly absorbs any water (e.g. bran)

Psyllium and bran are the two best-studied dietary fibers. While bran was not shown to relieve IBS symptoms in studies, research suggests that psyllium can help: Symptoms improved in 14 out of 100 people who had about 20 grams of psyllium in their diet per day.

Can dietary supplements relieve the symptoms?

Peppermint oil

Many people take peppermint oil capsules. This is supposed to relax the muscles of the intestine and have a calming effect on the intestine. Several studies have indeed shown that some people benefit from peppermint oil, at least temporarily: It relieved IBS symptoms in about 32 out of 100 people.

In these studies, peppermint oil was taken in capsules that are resistant to stomach acid. The dose used was between 500 and 800 mg per day. It is not clear whether taking peppermint oil in other forms, such as in solutions or drops, can help.

Some study participants had mild side effects from the peppermint oil capsules, such as heartburn or acid reflux. About 9 out of 100 people in the study were affected by those kinds of side effects.


In the gut flora there are different types of bacteria that play an important role in the intestine. These include lactic acid bacteria (LAB) and bifidobacteria. Some people with IBS have gut flora that have changed, so it is thought that probiotics containing these bacteria might be able to help.

Some studies suggest that probiotics can help against IBS. They were found to relieve IBS symptoms in 14 out of 100 people. But more research is needed to be able to find out which type of bacteria helps the most and what dose is most effective. Probiotics are generally well tolerated. About 3 out of 100 people in studies had mild side effects like bloating from probiotics. Probiotics can sometimes lead to infections in people who have a weakened immune system.

What medications help relieve IBS?

Anti-cramping medications

People whose main symptom is cramps often use anti-cramping medications to relax the muscles of the intestines and relieve the pain. Anti-cramping medications are also called antispasmodics or spasmolytics. Many of these medications have not been studied enough for use in the treatment of IBS. But research suggests that four of them may help: butylscopolamine, cimetropium, pinaverium and otilonium. The antispasmodic mebeverine, often prescribed in Germany and other countries, has not been proven to help against IBS because there are not enough available research results.

Of the anti-cramping medications that have been shown to help, butylscopolamine is the only one that is available in Germany. One study found that this medication relieved IBS symptoms in 12 out of 100 people. Butylscopolamine is available in pharmacies without a prescription in Germany.

The possible side effects of anti-cramping medications include a dry mouth, dizziness and blurred vision. About 5 out of 100 people in studies reported these types of side effects. There were no serious side effects.

Medications for constipation or diarrhea

Medications for constipation or diarrhea can also be used, depending on which of these symptoms a person has. But there is hardly any research on how well these medications can relieve these symptoms in IBS. Many laxatives and anti-diarrhea medications are available in pharmacies without a prescription.

One disadvantage of these medications is that they might just replace one problem with another: Medication for diarrhea may cause constipation if its effect is too strong. In the same way, medication for relieving constipation can lead to diarrhea. It is important to make sure that the medications do not make the symptoms even worse in people who have alternating diarrhea and constipation.


Antibiotics are sometimes considered as a treatment option for people whose IBS causes diarrhea or flatulence. The best-studied antibiotic is called rifaximin. In Germany this drug is only approved for treating traveler’s diarrhea. Yet doctors can still prescribe it “off-label” after providing full information about that type of use. Off-label use means that a drug is used to treat a condition without being approved for that specific use. When a drug is prescribed off label, insurers will only cover the costs in specific cases.

In studies, rifaximin was shown to relieve IBS symptoms in 13 out of 100 people. But it is not clear whether it also has a positive effect in the long term. According to current recommendations, antibiotics should not be used too often because they can have various side effects, including allergic reactions, nausea and fungal infections. Also, improper use or overuse of antibiotics can contribute to bacteria becoming resistant to antibiotics, meaning that they will not be as effective in the future. Antibiotics affect the gut flora too, which can sometimes make IBS symptoms worse.


Sometimes IBS is treated with drugs that are normally used to treat depression. These include tricyclic antidepressants and selective serotonin reuptake inhibitors (SSRIs), which are prescription-only. In Germany, they are not approved for treating IBS, so they can only be used off-label.

There are different reasons why it is thought that certain antidepressants may help in IBS. For instance, some of these drugs are believed to have a pain-relieving effect. Some also influence the muscles of the digestive tract.

Research has shown that tricyclic antidepressants and SSRIs can help relieve IBS: They were found to relieve the symptoms in 22 out of 100 people who took these medications. But they are generally only considered if other treatments haven’t been successful.

Antidepressants can have various side effects. In the above-mentioned studies, 15 out of 100 people had side effects like loss of appetite, nausea, decreased sex drive and problems with orgasm. Some antidepressants can themselves lead to constipation or diarrhea.

Other drugs

Some 5-HT3 and 5-HT4 antagonists have been approved for the treatment of IBS in several countries. These drugs include alosetron and cilansetron, which have mostly been tested for the treatment of IBS with diarrhea, and tegaserod, which has mostly been tested for the treatment of IBS with constipation.

These drugs have not been approved for use in Germany. There are safety concerns because they have been associated with serious side effects such as heart attacks, strokes and problems with the blood supply to the bowel.

There is also another 5-HT4 antagonist called prucalopride. Its use in the treatment of chronic constipation in women has been approved in Germany since 2009, but only in people who have already tried conventional laxatives and have found that they do not help.

How effective are acupuncture, reflexology and enemas?

Other approaches used to treat IBS include acupuncture, reflexology and enemas (colon hydrotherapy).

Many people say that they feel better after having acupuncture. But a number of studies have shown that this is not due to the specific effects of acupuncture: It had no benefits over a "fake" treatment.

There is very little scientific research on reflexology and enemas as treatments for IBS. So it is not clear whether they are effective. Before having an enema, the associated risks should be considered. These include electrolyte imbalances, infections, damage to the intestinal wall and even intestinal perforation (a hole in the intestinal wall).

Are psychological treatments or hypnosis also an option?

Because it is suspected that psychological stress may contribute to IBS, relaxation techniques and stress management are sometimes used. There has not yet been enough research on whether these methods help. But some studies have suggested that a combination of relaxation techniques, stress management and biofeedback can help.

Psychological approaches such as cognitive behavioral therapy (CBT) are used to treat IBS too. This treatment aims to help you learn to cope better with the symptoms. There is some evidence that cognitive behavioral therapy can indeed help people with IBS: About 30 out of 100 people had fewer symptoms after having this kind of therapy. CBT requires a lot of patience and motivation, though. So it is mainly considered in people who have very severe symptoms.

Some people who have IBS try hypnotherapy. During a hypnotherapy session, you focus so intensely on a certain idea that you become unaware of the things around you and are more receptive to what your therapist tells you (“suggestions”). For the treatment of IBS, one example of such a suggestion is imagining that you have a healthy, well-functioning bowel. Research has indicated that hypnotherapy can relieve symptoms in some people for several months. Hypnotherapy improved symptoms in about 23 out of 100 study participants, at least temporarily.


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Bookshelf ID: NBK279415


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