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Grier Darnall

Mythbusters: Peppermint relives functional dyspepsia symptoms

April 3, 2010





In one year anywhere from 25% to 40% of all adults are affected by functional dyspepsia, although only roughly 20% seek treatment for it.  There are very few proven herbs or medicines to relieve the symptoms of this illness.  Scientists have been exploring the use of peppermint as a treatment for functional dyspepsia and, as research has shown, have confirmed a positive correlation between the consumption of medicinal peppermint and the alleviation of the symptoms of functional dyspepsia. (


What is functional dyspepsia?


Functional dyspepsia is a complicated name for a fairly simple ailment.  The term dyspepsia can often be substituted with the term indigestion.  A functional disease is one in which the muscles or nerves surrounding organs are not functioning properly.  In the case of functional dyspepsia, this means that the muscles and/or nerves surrounding the stomach and intestines are not functioning properly, causing a chronically upset stomach.

        Common symptoms of functional dyspepsia include upper abdominal pain, belching, nausea, early satiety (or feeling full more quickly), and possibly abdominal distention, which is the swelling, not bloating, of the stomach.

        Functional dyspepsia can be caused by a number of things including the foods consumed and indigestion, a bacterial overgrowth in the small intestine, or visceral hypersensitivity.  Visceral hypersensitivity occurs when prior illness or ailment leaves the nerves surrounding an organ permanently damaged so that they perceive normal activity as painful. (   



Peppermint background check


        Peppermint is an herb that is grown in moist and temperate areas.  Tiny purple flowers bloom on the plant; however, it is the leaves and stem that are used commercially for their methanol, valued for its scent and numbing effects.  There are three main uses for peppermint in a commercial market: cosmetic, medicinal, and flavor enhancing.

        The first use of peppermint in a commercial market is in cosmetics, where the peppermint scent is used to create various perfumes and colognes as well as soaps.  These products are sold on a worldwide market for their ability to produce a good smell, which can in turn be applied to the body.

        A second use of peppermint is in flavoring of various foods and other products.  The famous mint obviously utilizes peppermint flavoring.  Other products that rely on the presence of peppermint are toothpaste, mouthwash, breath freshener, and gum.  These products also capitalize on the smell of the herb as well as the taste, which is considered refreshing and stimulating.

        The last and most important use of peppermint as it relates to functional dyspepsia is in medicine.  Traditionally peppermint has been used to treat various illnesses including stomach-associated illnesses such as functional dyspepsia, irritable bowel syndrome, and flatulence relief.  This herb is also known to alleviate the symptoms of the common cold by being applied to the chest as a cream; the smell clears the nasal passages.  Peppermint can also alleviate headaches due to the numbing potential of the methanol present within the plant.  Methods or application of peppermint vary and include creams, as in the chest rub, enteric-coated capsules or pills, and herbal teas. (



What’s the research?


        There are many online sources that affirm that peppermint is an effective treatment for functional dyspepsia.

        One article, written by New Zealand health officials intending to provide information on new breakthroughs in medicine for the New Zealand public, discusses the recent authorization by the German Commission E of the use of oral peppermint oil as a treatment for pain in the stomach and digestive tract.  The peppermint, whose primary ingredient of methanol is thought to be the main source of pain relief, relaxes the muscles in the small intestine in proportions as low as 50 parts per million.  Since the German health council has approved the measure, the scientific data behind their decision is extensive and thus opens up the pathway for other countries to officially authorize the medicinal use of peppermint for treatment of functional dyspepsia and other digestive and intestinal ailments. (

        Another article states that at least forty plants, of which peppermint is one, have been approved in France for the treatment of functional dyspepsia and other stomach ailments.  Although extensive research has not been conducted as to the efficacy of herbs such as peppermint, the few randomized controlled studies show that peppermint oils are effective in relieving dyspepsia symptoms such as diarrhea, flatulence, and intense abdominal pain.  Furthermore, there are no known health risks associated with peppermint oil and tea in medicinal uses. (



Is this backed up by science?


        According to many sources, functional dyspepsia is difficult to diagnose and treat.  Therefore it is also difficult to know the exact causes and prevalence of the illness.  One review claims that, in observing 21 studies of the prevalence of functional dyspepsia, the prevalence falls somewhere in the 12-15% range.  The causes of the illness, however, are more difficult to determine.  Most studies conclude that the presence of the bacteria H. pylori plays into the prevalence of functional dyspepsia while others point to nerve malfunctions in the stomach with regards to the digestion of food.  Although the article makes these conclusions, it also directly states that more studies and research are required in order to assure the data is correct, as some of the studies are inconsistent, and it suggests population-based studies as the solution to this lack of information. (

One study was done to compare the efficacy of peppermint oil with a common treatment for functional dyspepsia, casipride.  A group of 118 individuals plagued by functional dyspepsia were gathered for the experiment.  Of these, 60 patients were treated for the illness with a pill comprised of a combination of peppermint oil and caraway oil.  These pills were administered twice daily and contained 90 mg of peppermint oil and 50 mg of caraway oil.  The other experimental group was given two capsules of casipride daily.  The results were based on the reduction of the pain score.  In the group who took the peppermint/caraway oil combination pill the mean pain score was reduced by 4.62 points, whereas the group who was treated with the casipride had a lower pain score by 4.16 points.  Therefore, the experiment concludes that peppermint oil is an effective treatment for the symptoms of functional dyspepsia more so than already approved treatment methods.  There were few adverse reactions in either experimental group, 12 in the peppermint and caraway oil combination and 14 in the casipride group. (

        A similar study conducted by the Germans used a group of 39 patients affected by at least two symptoms of functional dyspepsia who were treated with either a pill that was a combination of peppermint oil and caraway oil in a ratio of 90:50 mg or a placebo three times a day for four weeks.  At the end of the test period, 85% of patients in the peppermint group reported reduction on abdominal pain and 94.5% had diminished gastrointestinal symptoms.  In contrast, at the end of the test period 45% of the patients in the placebo group reported reduced pain and 55% had reduced gastrointestinal symptoms with no side effects noted for either test group.  These results lead to the conclusion that peppermint oil, in combination with caraway oil, is a more effective treatment for functional dyspepsia than placebo. (



What does all this mean?


        All these studies lead to the conclusion that peppermint oil, many times in combination with other oils such as caraway oil, provides an effective treatment for the symptoms of functional dyspepsia.

        One primary research paper affirms that peppermint oil in combination with caraway oil has proven to work in treatment of the symptoms of functional dyspepsia, namely the reduction of gastrointestinal pressure and bloating.  It states that this is most likely due to peppermint’s calming and relaxing effects on the lower esophageal sphincter.  This table, referred to in the article, displays the efficacy of peppermint for different stomach disorders including functional dyspepsia and discusses the potential side effects, dosage, and use of the herb as a treatment option.


Key Points About Peppermint Oil



Irritable bowel syndrome symptoms: probably effective


Non-ulcer dyspepsia: probably effective


Reducing spasm during gastrointestinal procedures: probably effective


Tension headache: probably effective

Adverse effects

Common: allergic reactions, heartburn, perianal burning, blurred vision, nausea, and vomiting


Rare: interstitial nephritis, acute renal failure


May inhibit the cytochrome P450 1A2 system


Hiatal hernia, severe gastroesophageal reflux, gallbladder disorders; use with caution in pregnant and lactating women


Adults: 0.2 to 0.4 mL of oil three times daily in enteric-coated capsules


Children older than eight years: 0.1 to 0.2 mL three times daily


$24 to $32 for one-month supply

Bottom line

Safe at proper dosages and moderately effective in patients with functional gastrointestinal conditions




How safe is medicinal peppermint use?


        In all the conducted studies there have been little to no sign of adverse side effects reported, but as with every new treatment or medication there are possible associated risks.  Peppermint oil has no known side effects in small dosages, but with large medicinal uses the possible side effects include heartburn, rash or other allergic reaction, headache, dizziness, and difficulty breathing.  The FDA does not endorse the sale of peppermint oil or peppermint products for medical use because the volume of research on the safety and efficacy of the herb as a treatment for illness is not large enough to be entirely conclusive.  However, considering the fact that adverse side effects to the medicinal consumption of peppermint have shown up in very few and nonthreatening instances in studies, it is considered relatively safe. (

        Additionally, it should be noted that both in France and Germany peppermint as a treatment option has been approved and supported by the government and health officials. (



Conclusion and Recommendations


The use of peppermint products as treatment for the alleviation of dyspepsia symptoms should be further tested and studied in order to determine both its effectiveness and safety.  However, in accordance with the research that has been done to date and the fact that serious side effects have not been noted in any studies involving the medicinal use of peppermint, a patient suffering from functional dyspepsia should be able to rely on peppermint oil as a treatment option for the symptoms of the illness.

        Functional dyspepsia can be confused with some other more serious medical conditions such as stomach ulcers.  A patient who continues to feel pain after taking peppermint medical products should consult their doctor and have an upper gastrointestinal endoscopy in order to determine if other medical conditions are present.




Works Cited


Chaudhary, Sapna and Benjamin Kligler, MD.  “Peppermint Oil.”  American Academy of Family Physicians: 2007.  <>.

El-Serag, H.B. and N.J. Talley.  “The Prevalence and Clinical Course of Functional Dyspepsia: Discussion.”  Alimentary Pharmacology and Therapeutics: 2004.  <>.

Faster, Steven.  “Herbs for Health: Herbal Treatment for Dyspepsia.”  Ogden: 2010.  <>.

“Herbal remedies for dyspepsia: peppermint seems effective.”  U.S. National Library of Medicine: 2008.  <>.

Heydenreich, C., J. Hotz, R. Hufnagel, and A. Madisch.  “Treatment of functional dyspepsia with a fixed peppermint oil and caraway oil combination preparation as compared to cisapride : A multicenter, reference-controlled double-blind equivalence study.” Arzneimittel-Forschung.  1999.  <>.

Marks, Jay W., MD.  Ed. by William C. Shiel Jr. MD.  “Indigestion (Dyspepsia, Upset Stomach).”  MedicineNet: 2010.  <>.

Peppermint (Mentha x piperita L.).”  Natural Standard Research Collaboration: 2009.  <>.

“Peppermint Oil to Ease Stomach Distress.”  The Natural Health Clinic: 2006. <>.

“Peppermint.”  University of Maryland Medical Center: 2009. <>.





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