Enteric-coated peppermint oil (ECPO) has been shown to be quite helpful in the treatment of irritable
bowel syndrome (IBS) in several double-blind clinical studies. IBS is a disorder of the large intestine
characterized by some combination of abdominal pain, constipation or diarrhea, hypersecretion of
colonic mucus and symptoms of indigestion (flatulence, nausea and loss of appetite).
In the double-blind studies, ECPO has been shown to be effective in relieving all symptoms of IBS in
approximately 70-85% of cases within a two to four week period.
How Does It Work?
One of the central findings in IBS is a hypercontractility (excessive contraction) of intestinal smooth
muscle. Peppermint oil inhibits the hypercontractility of intestinal smooth muscle making it also useful
in cases of intestinal colic. In addition to its effects directly on intestinal smooth muscle, peppermint
oil also exerts significant effects against Candida albicans – a common yeast implicated in many
cases of IBS – as well as inhibits gallbladder contraction and emptying.
The two most recent double-blind studies of enteric-coated peppermint oil in IBS showed impressive
results. In one study, results showed that 75% of the patients in the ECPO group showed a >50%
reduction of total irritable bowel syndrome symptoms score compared with 38% in the placebo
group. In the other study of 90 outpatients with IBS, the severity of abdominal pain was also reduced
significantly in the ECPO group compared to the placebo group and more than twice as many
patients in the ECPO group showed complete symptom relief.