New peppermint oil formulation helps quiet IBS symptoms

A new formulation of peppermint oil, which will be available in June in major drug store chains, has been shown to relieve severe irritable bowel syndrome (IBS) symptoms in adults, including abdominal pain and bloating, reported Brooks D. Cash, MD, during the Digestive Disease Week annual meeting.

See also: FDA approves two new IBS-D treatments

 A medical food for the dietary management of IBS, IBgard, developed by IM HealthScience, is made of individually enteric-coated sustained-release microspheres of ultra-purified peppermint oil. It contains the active ingredient L-menthol that has calcium channel blocking activities and acts as a smooth muscle relaxant or an antispasmotic, according to Cash, professor of medicine at the University of South Alabama, Mobile, AL.

Brooks D. Cash“We primarily believe it works through its antispasmotic activity to ease abdominal pain and bloating,” explained Dr. Cash in an interview with Drug Topics. “There are multiple other mechanisms that have been shown to be possibly having an effect with peppermint oil, [such as anti-infectious and anti-inflammatory properties as well as carminative and serotonergic activity].”

The ultra-purified peppermint oil is embedded in a solid matrix of cellulose and covered with an inner seal coat to trap the terpenes in the peppermint oil. The middle coat is a pH release coating and the outmost coat is a non-muco adhesive coat, which allows the microparticulates to leave the stomach and enter the small bowel. See illustration for details.

This site-specific technology helps deliver the peppermint oil to the small intestine, which distinguishes it from other formulations on the market, Cash noted.

  IBSREST trial results

Illustration of IBgard, a new formulation of peppermint oil, delivered to the small intestine for relief of irritable bowel syndrome symptoms. (Courtesy of IM HealthScience)The Irritable Bowel Syndrome Reduction, Evaluation and Safety Trial (IBSREST) was undertaken to evaluate the safety and efficacy of IBgard, compared with placebo. Seventy-two patients with IBS associated with diarrhea (IBS-D) or IBS associated with diarrhea and constipation (IBS-M) were randomized to a 180 mg dose of IBgard three times daily or placebo for four weeks. IBS symptoms were reported by the patients in both groups.

At four weeks, patients in the IBgard group had greater reduction of IBS symptoms, including frequency and intensity of abdominal pain, bloating, pain at evacuation, and urgency, compared with the placebo-treated group, Cash noted.

Patients in the IBgard group reported a 66% reduction in the number of severe and unbearable symptoms (average of frequency and intensity ≥3 on a scale of 0 to 4) at four weeks, compared with a 42% reduction in the placebo group.

In addition, patients who received IBgard for four weeks reported almost an 80% reduction in abdominal pain intensity, compared to 40% in the placebo group.

“We believe that releasing the drug in the small intestine is fundamental to the activation of IBgard in terms of providing relief of IBS symptoms,” Cash said.

Other over-the-counter formulations of peppermint oil, such as a gel cap filled with the liquid, have been demonstrated to cause severe heartburn and dyspepsia in some patients, and others have reported anal burning and lower GI symptoms, he said.

This is not the case with IBgard, Cash said. There was only one patient in the IBSREST trial that reported dyspepsia, but that patient did not discontinue therapy.