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.

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.

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

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)

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.

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.

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.

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