Several can be recommended as part of an evidence-based approach to treating irritable bowel syndrome (IBS), according to researchers from the University of Ottawa in Ontario.


  • Overall, studies indicate improvement of global symptoms, especially constipation.
  • No improvement in abdominal pain.

Peppermint oil

  • 3 to 6 enteric-coated capsules daily (0.2 to 0.4 mL) improve symptoms.
  • Don’t chew the capsules, they’re enteric coated to prevent gastroesophageal reflux.
  • Nausea and burning around the anus and are occasional side effects.
  • Safety during pregnancy isn’t known.

Herbal formulas

  • Combining herbs is common.
  • Tong xie yao fang (TXYF) is possibly effective, but studies are of poor quality.
  • Padma Lax was better than placebo in 1 study.
  • STW 5 and STW 5–II significantly aided digestion and improved pain and symptom control in 1 study.
  • A Cochrane review concluded that certain formulations of TXYF, Padma Lax, and STW 5 improved global symptoms.
  • Adverse events occurred in 3% of patients — none serious.
  • Higher quality studies are needed to clarify the role of herbal formulas.


  • Patients should be encouraged to eat more probiotic-rich foods.
  • Taking capsules or powders might be beneficial, but commercial probiotics vary in strains used, quality, and ability to deliver enough live bacteria to the colon.

Mind-body therapies

  • Hypnotherapy and cognitive behavioral therapy (CBT) are supported most by the evidence among mind-body therapies.


  • Current evidence doesn’t support its use.

The bottom line?
The authors concluded, “Current drug therapy often provides inadequate relief of IBS symptoms, leading many patients to consider CAM therapies. Peppermint oil and probiotics are supported by enough evidence to recommend their use.”

2/22/09 19:33 JR

Hi, I’m JR

John Russo, Jr., PharmD, is president of The MedCom Resource, Inc. Previously, he was senior vice president of medical communications at, a complementary and alternative medicine website.