This information is for people who have irritable bowel syndrome. It tells you about peppermint oil, a treatment used for irritable bowel syndrome.
We haven't looked at the research on this treatment in as much detail as we have for other treatments on our site (see Our method for more information). But we've included some information because you may have heard of this treatment or be interested in it.
Peppermint oil relaxes the muscles in your bowels.   It may improve symptoms of IBS, including pain and bloating.
You can get peppermint oil capsules on prescription from your doctor. You can also buy peppermint oil yourself in a pharmacy as Colpermin capsules or Mintec capsules.
You should swallow the capsules whole with water. You shouldn't break or chew them because they can irritate your mouth.
Although peppermint oil is often used to treat IBS, there's not a lot of research to show whether it works. We found several summaries of the research on peppermint oil.   They found that peppermint oil was better at reducing symptoms than a dummy treatment (a placebo).
A recent review combined several studies looking at nearly 400 people with IBS.  About 74 in 100 people improved with peppermint oil, compared with 35 in 100 people who took a placebo.
There may be side effects from peppermint oil. In some of the studies, around 2 in 10 people got at least one side effect.  These included:
A placebo is a 'pretend' or dummy treatment that contains no active substances. A placebo is often given to half the people taking part in medical research trials, for comparison with the 'real' treatment. It is made to look and taste identical to the drug treatment being tested, so that people in the studies do not know if they are getting the placebo or the 'real' treatment. Researchers often talk about the 'placebo effect'. This is where patients feel better after having a placebo treatment because they expect to feel better. Tests may indicate that they actually are better. In the same way, people can also get side effects after having a placebo treatment. Drug treatments can also have a 'placebo effect'. This is why, to get a true picture of how well a drug works, it is important to compare it against a placebo treatment.
For more terms related to Irritable bowel syndrome
For references related to Irritable bowel syndrome click here