Botanical Name: Mentha x piperita

Overview
Plant Description
What's It Made Of?
Available Forms
How to Take It
Precautions
Possible Interactions
Supporting Research

Overview

Peppermint (Mentha x piperita), a popular flavoring for gum, toothpaste, and tea, also serves as a calming agent to soothe an an upset stomach or to aid in digestion. Because it has a calming and numbing effect, it has been used to treat headaches, skin irritations, anxiety associated with depression, nausea, diarrhea, menstrual cramps, and flatulence. It is also widely used to treat symptoms of the common cold. These and other conditions for which peppermint may be beneficial are listed below.

Indigestion
Peppermint calms the muscles of the stomach and improves the flow of bile, which the body uses to digest fats. As a result, food passes through the stomach more quickly. It is important to know, however, if your symptoms of indigestion are related to a condition called gastoesophageal reflux disease or GERD, peppermint should not be used - see Precautions.

Flatulence/Bloating
Peppermint relaxes the muscles that allow the body to rid itself of painful digestive gas.

Irritable Bowel Syndrome (IBS)
A number of studies have shown the beneficial effects of enteric-coated peppermint capsules for treating symptoms of IBS, such as pain, bloating, gas, and diarrhea. (Enteric-coated capsules keep the oil from being released in the stomach, which can lead to heartburn and indigestion.) A recent study comparing enteric-coated peppermint oil capsules to placebo in children with IBS found that after 2 weeks, 75% of those treated had reduced symptoms. This is in keeping with an earlier study of adults in which 79% of participants receiving peppermint experienced a relief in the severity of pain.

Menstrual Cramps
Peppermint has the potential to influence menstrual periods and, because it relaxes muscles, may help to relieve painful cramps.

Gallstones
Peppermint oil may help the body break down gallstones.

Viruses
Peppermint oil has exhibited antiviral properties against a number of infectious agents, including herpes.

Itching and Skin Irritations
Peppermint, when applied topically, has a soothing and cooling effect on skin irritations caused by hives, poison ivy, or poison oak.

Tension Headache
Research has shown that peppermint applied to the forehead and temples compares favorably with acetaminophen (a commonly used over the counter medication) in terms of its ability to reduce headache symptoms.

Colds and Flu
Peppermint and its main active agent, menthol, are effective decongestants. Because menthol thins mucus, it is also a good expectorant, meaning that it helps loosen and breaks up coughs with phlegm. It is soothing and calming for sore throats (pharyngitis) and dry coughs as well.

 

Plant Description

Peppermint plants grow to about two feet tall. They bloom from July through August, sprouting tiny purple flowers in whorls and terminal spikes. Simple, toothed, and fragrant leaves grow opposite the flowers. Peppermint is native to Europe and Asia, is naturalized to North America, and grows wild in moist, temperate areas. Some varieties are indigenous to South Africa, South America, and Australia.


 

What's It Made Of?

Peppermint preparations start with the leaves and flowering tops of the plant. These contain a volatile oil, peppermint's primary active component, menthol.


 

Available Forms

Peppermint tea is prepared from dried leaves of the plant. Such teas are widely available commercially.

Peppermint spirit (tincture) in an alcoholic solution containing 10% peppermint oil and 1% peppermint leaf extract. A tincture can be prepared by adding 1 part peppermint oil to 9 parts pure grain alcohol.

Enteric-coated capsules, which are specially coated to allow the capsule to pass through the stomach and into the intestine (0.2 mL of peppermint oil per capsule)

Creams or ointments (should contain 1% to 16% menthol)

 

How to Take It

Pediatric

For digestion and upset stomach: 1 to 2 mL peppermint glycerite per day

Adult

Peppermint tea soothes an upset stomach and can aid digestion. It can be prepared using the infusion method of pouring boiling water over the herb and then steeping for 3 to 5 minutes. Use 1 to 2 tsp of dried peppermint leaf to 8 oz of hot water.

  • Irritable bowel syndrome: Take 1 to 2 coated capsules three times per day between meals.
  • Gallstones: Take 1 to 2 enteric-coated capsules three times per day between meals.
  • Itching and skin irritations: Apply menthol, the active ingredient in peppermint, in a cream or ointment form no more than three to four times per day.
  • Tension headaches: Using a tincture of 10% peppermint oil to 90% ethanol, lightly coat the forehead and allow the tincture to evaporate.
 

Precautions

The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, contain active substances that can trigger side effects and interact with other herbs, supplements, or medications. For these reasons, herbs should be taken with care, under the supervision of a practitioner knowledgeable in the field of botanical medicine.

Peppermint tea is generally a safe way to soothe an upset stomach. However, peppermint should not be used by those with gastoesophageal reflux disease (GERD -- a condition in which stomach acids back up into the esophagus) even though some of the symptoms include indigestion and heartburn. This is because peppermint can relax the sphincter between the stomach and esophagus, allowing stomach acids to flow back into the esophagus. (The sphincter is the muscle that separates the esophagus from the stomach.) By relaxing the sphincter, peppermint may actually worsen the symptoms of heartburn and indigestion.

Pregnant or nursing mothers should drink peppermint tea only in moderation and those with a history of miscarriage should not use peppermint at all while pregnant.

Rare negative reactions to enteric-coated peppermint oil capsules may include skin rash, slowed heart rate, and muscle tremors.

Menthol or peppermint oil applied to the skin can cause contact dermatitis or other type of rash, including, possibly hives. Some have described hot flashes from the oil. It should be kept away from the eyes and other mucus membranes and should not be inhaled by or applied to the face of an infant or small child. Peppermint oil should be diluted and taken in very small amounts, since it can cause negative reactions such as those listed above, cramping and diarrhea, as well as, rarely drowsiness, tremor, muscle pain, slowed heart rate, and, in severe cases of overdose, coma. Pure menthol is poisonous and should never be taken internally. It is important not to confuse oil and tincture preparations.

 

Possible Interactions

5-Fluorouracil for Cancer
In an animal study, topical peppermint oil increased the absorption of 5-fluorouracil, a medication used to treat cancer that was also applied topically. It is too early to draw conclusions about the applicability of these findings to people. Therefore, it would be wise to avoid applying peppermint oil topically when using other topical medications for cancer.

 

Supporting Research

Abdullah D, Ping QN, Liu G. Enhancing effect of essential oils on the penetration of 5-fluorouracil through rat skin. Yao Hsueh Hsueh Pao. 1996;31(3):214-221.

Blumenthal M, Goldberg A, Brinckmann J. Herbal Medicine: Expanded Commission E Monographs. Newton, MA: Integrative Medicine Communications; 2000:297-303.

Briggs CJ, Briggs GL. Herbal products in depression therapy. CPJ/RPC. November 1998;40-44.

Brinker F. Herb Contraindications and Drug Interactions. Sandy, Oregon: Eclectic medical Publications. 1998:111, 173-175.

Dew MJ, Evans BK, Rhodes J. Peppermint oil for the irritable bowel syndrome: a multicentre trial. Br J Clin Pract. 1984;(11-12):394, 398.

Gobel H, Schmidt G, Soyka D. Effect of peppermint and eucalyptus oil preparations on neurophysiological and experimental algesimetric headache parameters. Cephalalgia. 1994;14(3):228-234.

Hills J. The mechanism of action of peppermint oil on gastrointestinal smooth muscle. Gastroenterology. 1991;101:55-65.

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(1):125-128.

Koch TR. Peppermint oil and irritable bowel syndrome. Am J Gastroenterol. 1998;93:2304-2305.

Liu JH, Chen GH, Yeh HZ, Huang CK, Poon SK. Enteric-coated peppermint-oil capsules in the treatment of irritable bowel syndrome: a prospective, randomized trial.
J Gastroenterol. 1997;32(6):765-768.

Pittler MH, Ernst E. Peppermint oil for irritable bowel syndrome: a critical review and meta-analysis. Am J Gastroenterol. 1998;93(7):1131-1135.

Pizzorno JE, Murray MT. Textbook of Natural Medicine. New York: Churchill Livingstone; 1999:827-829, 1361-1362, 1558.

Robbers JE, Tyler VE. Herbs of Choice: The Therapeutic Use of Phytomedicinals. New York, NY: The Haworth Herbal Press; 1999: 67-68.

Woolf A. Essential oil poisoning. Clinical Toxicology. 1999;37(6):721-727.


Review Date: April 2002

Reviewed By: Participants in the review process include: Steven Dentali, PhD (April 1999), Senior Director of Botanical Science, Rexall Sundown, Boca Raton, FL; Jacqueline A. Hart, MD, Department of Internal Medicine, Newton-Wellesley Hospital, Harvard University and Senior Medical Editor Integrative Medicine, Boston, MA; Gary Kracoff, RPh (Pediatric Dosing section February 2001), Johnson Drugs, Natick, MA; Steven Ottariono, RPh (Pediatric Dosing section February 2001), Veteran's Administrative Hospital, Londonderry, NH; R. Lynn Shumake, PD, Director, Alternative Medicine Apothecary, Blue Mountain Apothecary & Healing Arts, University of Maryland Medical Center, Glenwood, MD; Tom Wolfe, P.AHG (March 1999), Smile Herb Shop, College Park, MD. All interaction sections have also been reviewed by a team of experts including Joseph Lamb, MD (July 2000), The Integrative Medicine Works, Alexandria, VA;Enrico Liva, ND, RPh (August 2000), Vital Nutrients, Middletown, CT; Brian T Sanderoff, PD, BS in Pharmacy (March 2000), Clinical Assistant Professor, University of Maryland School of Pharmacy; President, Your Prescription for Health, Owings Mills, MD; Ira Zunin, MD, MPH, MBA (July 2000), President and Chairman, Hawaii State Consortium for Integrative Medicine, Honolulu, HI.

The publisher does not accept any responsibility for the accuracy of the information or the consequences arising from the application, use, or misuse of any of the information contained herein, including any injury and/or damage to any person or property as a matter of product liability, negligence, or otherwise. No warranty, expressed or implied, is made in regard to the contents of this material. No claims or endorsements are made for any drugs or compounds currently marketed or in investigative use. This material is not intended as a guide to self-medication. The reader is advised to discuss the information provided here with a doctor, pharmacist, nurse, or other authorized healthcare practitioner and to check product information (including package inserts) regarding dosage, precautions, warnings, interactions, and contraindications before administering any drug, herb, or supplement discussed herein.


Botanical name: Mentha piperita

Parts used and where grown: Peppermint is a hybrid of water mint and spearmint and was first cultivated near London in 1750. Peppermint is now cultivated widely, particularly in the U.S. and Europe. The two main cultivated forms are the black mint, which has violet-colored leaves and stems and a relatively high oil content, and the white mint, which has pure green leaves and a milder taste. The leaves are used medicinally.

Peppermint has been used in connection with the following conditions (refer to the individual health concern for complete information):

Reliable and relatively consistent scientific data showing a substantial health benefit.
Contradictory, insufficient, or preliminary studies suggesting a health benefit or minimal health benefit.
An herb is primarily supported by traditional use, or the herb or supplement has little scientific support and/or minimal health benefit.

Historical or traditional use (may or may not be supported by scientific studies): Recognized in the early 18th century, the historical use of peppermint is not dramatically different than its use in modern herbal medicine. Classified as a carminative herb, peppermint has been used as a general digestive aid and employed in the treatment of indigestion and intestinal colic by herbalists.1

Active constituents: Peppermint leaves yield approximately 0.1-1.0% volatile oil which is composed primarily of menthol (29-48%) and menthone (20-31%).2 Peppermint oil is classified as a carminative (prevents and relieves intestinal gas).3 It may also relieve spasms in the intestinal tract. Peppermint oil or peppermint tea is often used to treat gas and indigestion.

Three double-blind trials found that enteric-coated peppermint oil reduced the pain associated with intestinal spasms, commonly experienced in irritable bowel syndrome (IBS).4 5 6 However, another trial found no effect of peppermint on IBS.7 A double-blind trial found that an enteric-coated combination of peppermint and caraway oils was superior to a placebo for people with gastrointestinal complaints including IBS.8 A combination of peppermint, caraway seeds, and two other carminative herbs (fennel seeds and wormwood) was reported to be effective for gastrointestinal complaints including IBS in another double-blind study.9

A tea of peppermint is a traditional therapy for colic in infants but has never been investigated in a human trial. Peppermint should be used cautiously in infants (see side effects below).

Peppermint oil's relaxing action also extends to topical use. When applied topically, it acts as an analgesic and reduces pain.10 A trial of topical peppermint oil applied to the temples of healthy volunteers (with or without eucalyptus oil) found that peppermint oil had a muscle-relaxing action and it decreased tension.11 Topical peppermint oil alone reduced pain in people with tension headaches as well.

How much is usually taken? For internal use, a tea can be made by pouring 1 cup (250 ml ) of boiling water over 1 heaped teaspoon (5 grams) of the dried leaves and steeping for five to ten minutes. Three to four cups (750-1000 ml) daily between meals can be taken to relieve stomach and gastrointestinal complaints.12 Peppermint leaf tablets and capsules, 3-6 grams per day, can be taken. For treatment of irritable bowel syndrome, 1-2 enteric-coated capsules containing 0.2 ml of peppermint oil taken two to three times per day is recommended.

For headaches, a combination of peppermint oil and eucalyptus oil diluted with base oil can be applied to the temples at the onset of the headache and every hour after that or until symptom relief is noted.

Are there any side effects or interactions? Peppermint tea is generally considered safe for regular consumption. Peppermint oil can cause burning and gastrointestinal upset in some people.13 It should be avoided by people with chronic heartburn, severe liver damage, inflammation of the gallbladder, or obstruction of bile ducts.14 People with gallstones should consult a physician before using peppermint leaf or peppermint oil. Some people using enteric-coated peppermint capsules may experience a burning sensation in the rectum. Rare allergic reactions have been reported with topical use of peppermint oil. Peppermint oil should not be applied to the face-in particular, the nose-of children and infants. Peppermint tea should be used with caution in infants and young children, as they may choke in reaction to the strong menthol. Chamomile is usually a better choice for this group for treating colic and mild gastrointestinal complaints.

Are there any drug interactions? Certain medications may interact with peppermint. Refer to the drug interactions safety check for a list of those medications.

References:
1. Foster S. Herbs for Your Health. Loveland, CO: Interweave Press, 1996, 72-3.

2. Bradley PR (ed). British Herbal Compendium, vol 1. Bournemouth, Dorset UK: British Herbal Medicine Association, 1992, 174-6.

3. Tyler VE. Herbs of Choice: The Therapeutic Use of Phytomedicinals. Binghamton, NY: Pharmaceutical Products Press, 1994, 56-7.

4. Dew MJ, Evans BK, Rhodes J. Peppermint oil for the irritable bowel syndrome: a multicenter trial. Br J Clin Pract 1984;38:394-8.

5. Liu J-H, Chen G-H, Yeh H-Z, et al. Enteric-coated peppermint-oil capsules in the treatment of irritable bowel syndrome: a prospective, randomized trial. J Gastroenterol 1997;32:765-8.

6. Rees W, Evans B, Rhodes J. Treating irritable bowel syndrome with peppermint oil. Br Med J 1979; 2:835-6.

7. Nash P, Gould SR, Barnardo DB. Peppermint oil does not relieve the pain of irritable bowel syndrome. Br J Clin Pract 1986;40:292-3.

8. May B, Kuntz HD, Kieser M, Kohler S. Efficacy of a fixed peppermint/caraway oil combination in non-ulcer dyspepsia. Arzneimittelforschung 1996;46:1149-53.

9. Westphal J, Hörning M, Leonhardt K. Phytotherapy in functional abdominal complaints: Results of a clinical study with a preparation of several plants. Phytomedicine 1996;2:285-91.

10. Göbel H, Schmidt G, Dwoshak M, et al. Essential plant oils and headache mechanisms. Phytomedicine 1995;2:93-102.

11. Göbel H, Schmidt G, Soyka DS. Effect of peppermint and eucalyptus oil preparations on neurophysiological and experimental algesimetric headache parameters. Cephalalgia 1994;14:228-34.

12. Wichtl M. Herbal Drugs and Phytopharmaceuticals. Boca Raton, FL: CRC Press, 1994, 336-8.

13. Sigmund DJ, McNally EF. The action of a carminative on the lower esophageal sphincter. Gastroent 1969;56:13-8.

14. Blumenthal M, Busse WR, Goldberg A, et al. (eds). The Complete Commission E Monographs: Therapeutic Guide to Herbal Medicines. Boston, MA: Integrative Medicine Communications, 1998, 180-2.