Enteric-coated peppermint oil has been shown to be quite helpful in improving gastrointestinal function in individuals suffering from the irritable bowel syndrome (IBS) - a common functional disorder of the large intestine characterized by some combination of: (1) abdominal pain, (2) altered bowel function, constipation, or diarrhea, (3) hypersecretion of colonic mucus, (4) dyspeptic symptoms (flatulence, nausea, anorexia), and (5) varying degrees of anxiety or depression.

In several double-blind studies, enteric-coated peppermint oil (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. In the latest trial, 42 children between 8-10 years old with IBS were given ECPO or placebo for 2 weeks. Dosage was one capsule three times daily for children 30-45 kg and two capsules three times daily for children over 45 kg. After 2 weeks, 76% of the ECPO group reported significant improvements compared to only 19% in the placebo group.1

One of the central findings in IBS is a hypercontractility (excessive contraction) of intestinal smooth muscle. Peppermint oil, especially when combined with caraway oil, inhibits the hypercontractility of intestinal smooth muscle making it useful in cases of the irritable bowel syndrome as well as esophageal spasm and intestinal colic.2

Other uses

In addition to its effects in IBS, enteric-coated peppermint oil exerts benefits in non-ulcer dyspepsia, gastro-esophageal reflux disorder, intestinal overgrowth of Candida albicans (a common yeast implicated in many cases of IBS) and Helicobacter pylori (a bacteria linked to peptic ulcer disease and stomach cancer), and cases of gallstones.

Non-ulcer dyspepsia (NUD) as well as gastro-esophageal reflux disorder (GERD) are basically catch-all terms that reflect kind of waste-basket diagnosis doctors use when they cannot find any real reason for a patient’s upper GI dysfunction, just as irritable bowel syndrome (IBS) is used as a waste basket diagnosis for lower GI dysfunction. Symptoms of NUD and GERD include heartburn as well as difficulty swallowing, feelings of pressure or heaviness after eating, sensations of bloating after eating, stomach or abdominal pains and cramps, as well as all of the symptoms of IBS. About three out of ten patients with NUD and GERD also meet the criteria for IBS.

Caraway oil and oregano oil can enhance the benefits of peppermint oil

Several of the clinical studies in patients with IBS featured the combination of peppermint oil and caraway oil. The results of these trials indicate that this combination produces better results than peppermint oil alone in symptoms of IBS. Recent studies also indicate the combination of peppermint and caraway oil is quite helpful in improving non-ulcer dyspepsia (NUD).3,4 In one double-blind study, 120 patients with NUD were given either the peppermint and caraway seed oil or cisapride (Propulsid) for 4 weeks.4 The mean reduction of pain score was comparable in both groups (4.62 for ECPO; 4.6 cisparide). Other symptoms of NUD also improved in a similar fashion. Positive results were also found in H. pylori positive individuals.

The significance of this study is ENORMOUS. While enteric-coated peppermint and caraway oil is extremely safe at recommended levels, Propulsid caused fatal heart rhythm problems. According to the United States Food and Drug Administration, at least 111 people died as a result of Propulsid use and nearly 400 developed heart abnormalities. Propulsid has subsequently been yanked off the market.

Even more effective than enteric-coated peppermint and caraway oil preparations are those that also contain oregano oil as well such as Natural Factors’ Peppermint Oil Complex. Oregano oil is among the most popular anti-candida recommendations by many natural health experts. The volatile oils from oregano, caraway, and peppermint are all effective antifungal agents. One study compared the anti-Candida effect of oregano oil to caprylic acid and found that the anti-Candida activity of oregano oil is greater than 100 times more potent than caprylic acid.5

Enteric-coated peppermint oil also help gallstones

Several studies have shown a combination of volatile oils can help dissolve gallstones.6 This approach to gallstone removal is not effective in all cases, but it does offer the opportunity for an effective alternative to surgery. The major components of the formula used in these studies, was menthol and carvone – the major components of peppermint oil and caraway oil, respectively.

Dosage and safety information

The usual dosage of enteric-coated capsules containing peppermint, caraway, and oregano oil is 1-2 capsules (200 mg/capsule) up to three times daily between meals. Side effects are rare, but can include allergic reactions (skin rash), heartburn, and if the dosage is too high a burning sensation upon defecation. There are no known drug interactions.

 

References:

1. Kline RM, Kline JJ, Di Palma J, Barbero GJ. Enteric-coated, pH-dependent peppermint oil capsules for the treatment of irritable bowel syndrome in children. J Pediatr 2001;138:125-8.
2. Micklefield GH, Greving I, May B. Effects of peppermint oil and caraway oil on gastroduodenal motility. Phytother Res 2000;14:20-3.
3. May B, Kuntz HD, Kieser M, et al: Efficacy of a fixed peppermint oil/caraway oil combination in non-ulcer dyspepsia. Arzneim Forsch 1996;46:1149-53.
4. May B, Kohler S, Schneider B. Efficacy and tolerability of a fixed combination of peppermint oil and caraway oil in patients suffering from functional dyspepsia. Aliment Pharmacol Ther 2000;14:1671-7.
5. Stiles JC, Sparks W, Ronzio RA. The inhibition of Candida albicans by oregano. J Applied Nutr 1995;47:96-102.
6. Somerville KW, Ellis WR, Whitten BH, et al: Stones in the common bile duct: experience with medical dissolution therapy. Postgrad Med J 1985;61:313-6.
   

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Michael T. Murray, N.D., is widely regarded as one of world's leading authorities on natural medicine. A prolific author, Dr. Murray has written over 20 books on health and nutrition including the best-selling Encyclopedia of Natural Medicine and his latest book The Encyclopedia of Healing Foods. Dr. Murray is also Director of Product Development and Education for Natural Factors one of the leading manufacturers of natural products.